part i

., 1904, ii., 1907, iii., 1907, by Don Martino de Silva Wickremasinghe, who in 1899 was appointed epigraphist to the Ceylon government. Among other works on special subjects may be mentioned H. Trimen, F.R.S., director of Ceylon Botanic Gardens, _Ceylon Flora_, in 5 vols., completed by Sir Joseph Hooker; Captain V. Legge, F.Z.S., _History of the Birds of Ceylon_ (London, 1870); Dr Copleston, bishop of Colombo, _Buddhism, Primitive and Present, in Magadha and in Ceylon_ (London, 1892); review by Sir West Ridgeway, _Administration of Ceylon, 1896-1903_; Professor W.A. Herdman, _Report on the Pearl Oyster Fisheries, 1903-1904_.

CHABAZITE, a mineral species belonging to the group of zeolites. It occurs as white to flesh-red crystals which vary from transparent to translucent and have a vitreous lustre. The crystals are rhombohedral, and the predominating form is often a rhombohedron (r) with interfacial angles of 85 deg. 14'; they therefore closely resemble cubes in appearance, and the mineral was in fact early (in 1772) described as a cubic zeolite. A characteristic feature is the twinning, the crystals being frequently interpenetration twins with the principal axis as twin-axis (figs, 1, 2). The appearance shown in fig. 1, with the corners of small crystals in twinned position projecting from the faces r of the main crystal, is especially characteristic of chabazite. Such groups resemble the interpenetrating twinned cubes of fluorspar, but the two minerals are readily distinguished by their cleavage, fluorspar having a perfect octahedral cleavage truncating the corners of the cube, whilst in chabazite there are less distinct cleavages parallel to the rhombohedral (cube-like) faces. Another type of twinned crystal is represented in fig. 2, in which the predominating form is an obtuse hexagonal pyramid (t); the faces of these flatter crystals are often rounded, giving rise to lenticular shapes, hence the name phacolite (from [Greek: phakos], a lentil) for this variety of chabazite.

[Illustration: FIG. 1. FIG. 2. Twinned Crystals of Chabazite.]

The hardness of chabazite is 4-1/2, and the specific gravity 2.08-2.16. As first noticed by Sir David Brewster in 1830, the crystals often exhibit anomalous optical characters: instead of being uniaxial, a basal section may be divided into sharply-defined biaxial sectors. Heating of the crystals is attended by a loss of water and a change in their optical characters; it is probable therefore that the anomalous optical characters are dependent on the amount of water present.

Besides phacolite, mentioned above, other varieties of chabazite are distinguished. Herschelite and seebachite are essentially the same as phacolite. Haydenite is the name given to small yellowish crystals, twinned on a rhombohedron plane r, from Jones's Falls near Baltimore in Maryland. Acadialite is a reddish chabazite from Nova Scotia (the old French name of which is Acadie).

Chemically, chabazite is a complex hydrated calcium and sodium silicate, with a small proportion of the sodium replaced by potassium, and sometimes a small amount of the calcium replaced by barium and strontium. The composition is however variable, and is best expressed as an isomorphous mixture of the molecules (Ca, Na2) Al2(SiO4)2 + 4H2O and (Ca, Na2) Al2(Si3O8)2 + 8H2O, which are analogous to the felspars. Most analyses correspond with a formula midway between these extremes, namely, (Ca, Na2)Al2(SiO3)4 + 6H2O.

Chabazite occurs with other zeolites in the amygdaloidal cavities of basaltic rocks; occasionally it has been found in gneisses and schists. Well-formed crystals are known from many localities; for example, Kilmalcolm in Renfrewshire, the Giant's Causeway in Co. Antrim, and Oberstein in Germany. Beautiful, clear glassy crystals of the phacolite ("seebachite") variety occur with phillipsite and radiating bundles of brown calcite in cavities in compact basalt near Richmond, Melbourne, Victoria. Small crystals have been observed lining the cavities of fossil shells from Iceland, and in the recent deposits of the hot springs of Plombieres and Bourbonne-les-Bains in France.

Gmelinite and levynite are other species of zeolites which may be mentioned here, since they are closely related to chabazite, and like it are rhombohedral and frequently twinned. Gmelinite forms large flesh-red crystals usually of hexagonal habit, and was early known as soda-chabazite, it having the composition of chabazite but with sodium predominating over calcium (Na2, Ca)Al2(SiO3)46H2O. The formula of levynite is CaAl2Si3O10 + 5H2O. (L. J. S.)

CHABLIS, a town of north-central France, in the department of Yonne, on the left bank of the Serein, 14 m. E. by N. of Auxerre by road. Pop. (1906) 2227. Its church of St Martin belongs to the end of the 12th century. The town gives its name to a well-known white wine produced in the neighbouring vineyards, of which the most esteemed are Clos, Bouguerots, Moutonne, Grenouille, Montmaires, Lys and Vaux-Desirs. There are manufactures of biscuits.

CHABOT, FRANCOIS (1757-1794), French revolutionist, had been a Franciscan friar before the Revolution, and after the civil constitution of the clergy continued to act as "constitutional" priest, becoming grand vicar of Henri Gregoire, bishop of Blois. Then he was elected to the Legislative Assembly, sitting at the extreme left, and forming with C. Bazire and Merlin de Thionville the "Cordelier trio." Re-elected to the Convention he voted for the death of Louis XVI., and opposed the proposal to prosecute the authors of the massacre of September, "because among them there are heroes of Jemmapes." Some of his sayings are well known, such as that Christ was the first "_sans-culotte_." Compromised in the falsification of a decree suppressing the India Company and in a plot to bribe certain members of the Convention, especially Fabre d'Eglantine and C. Bazire, he was arrested, brought before the Revolutionary Tribunal, and was condemned and executed at the same time as the Dantonists, who protested against being associated with such a "_fripon_."

CHABOT, GEORGES ANTOINE, known as CHABOT DE L'ALLIER (1758-1819), French jurist and statesman, was president of the tribunal of Montlucon when he was elected as a deputy _suppleant_ to the National Convention. A member of the council of the Ancients, then of the Tribunate, he was president of the latter when the peace of Amiens was signed. He had a resolution adopted, tending to give Napoleon Bonaparte the consulship for life; and in 1804 supported the proposal to establish a hereditary monarchy. Napoleon named him inspector-general of the law schools, then judge of the court of cassation. He published various legal works, e.g. _Tableau de la legislation ancienne sur les successions et de la legislation nouvelle etablie par le code civil_ (Paris, 1804), and _Questions fransitoires sur le code Napoleon_ (Paris, 1809).

CHABOT, PHILIPPE DE, SEIGNEUR DE BRION, COUNT OF CHARNY AND BUZANCAIS (c. 1492-1543), admiral of France. The Chabot family was one of the oldest and most powerful in Poitou. Philippe was a cadet of the Jarnac branch. He was a companion of Francis I. as a child, and on that king's accession was loaded with honours and estates. After the battle of Pavia he was made admiral of France and governor of Burgundy (1526), and shared with Anne de Montmorency the direction of affairs. He was at the height of his power in 1535, and commanded the army for the invasion of the states of the duke of Savoy; but in the campaigns of 1536 and 1537 he was eclipsed by Montmorency, and from that moment his influence began to wane. He was accused by his enemies of peculation, and condemned on the 10th of February 1541 to a fine of 1,500,000 livres, to banishment, and to the confiscation of his estates. Through the good offices of Madam d'Etampes, however, he obtained the king's pardon almost immediately (March 1541), was reinstated in his posts, and regained his estates and even his influence, while Montmorency in his turn was disgraced. But his health was affected by these troubles, and he died soon afterwards on the 1st of June 1543. His tomb in the Louvre, by an unknown sculptor, is a fine example of French Renaissance work. It was his nephew, Guy Chabot, seigneur de Jarnac, who fought the famous duel with Francois de Vivonne, seigneur de la Chataigneraie, in 1547, at the beginning of the reign of Henry II.

The main authorities for Chabot's life are his MS. correspondence in the Bibliotheque Nationale, Paris, and contemporary memoirs. See also E de Barthelemy, "Chabot de Brion," in the _Revue des questions historiques_ (vol. xx. 1876); Martineau, "L'Amiral Chabot," in the _Positions des theses de l'Ecole des Chartes_ (1883).

CHABRIAS (4th century B.C.), a celebrated Athenian general. In 388 B.C. he defeated the Spartans at Aegina and commanded the fleet sent to assist Evagoras, king of Cyprus, against the Persians. In 378, when Athens entered into an alliance with, Thebes against Sparta, he defeated Agesilaus near Thebes. On this occasion he invented a manoeuvre, which consisted in receiving a charge on the left knee, with shields resting on the ground and spears pointed against the enemy. In 376 he gained a decisive victory over the Spartan fleet off Naxos, but, when he might have destroyed the Spartan fleet, remembering the fate of the generals at Arginusae, he delayed to pick up the bodies of his dead. Later, when the Athenians changed sides and joined the Spartans, he repulsed Epaminondas before the walls of Corinth. In 366, together with Callistratus, he was accused of treachery in advising the surrender of Oropus to the Thebans. He was acquitted, and soon after he accepted a command under Tachos, king of Egypt, who had revolted against Persia. But on the outbreak of the Social War (357) he joined Chares in the command of the Athenian fleet. He lost his life in an attack on the island of Chios.

See Cornelius Nepos, _Chabrias_; Xenophon, _Hellenica_, v. 1-4; Diod. Sic. xv. 29-34; and C. Rehdantz, _Vitae Iphicratis, Chabriae, et Timothei_ (1845); art. DELIAN LEAGUE, section B, and authorities there quoted.

CHABRIER, ALEXIS EMMANUEL (1841-1894), French composer, was born at Ambert, Puy de Dome, on the 18th of January 1841. At first he only cultivated music as an amateur, and it was not until 1879 that he threw up an administration appointment in order to devote himself entirely to the art. He had two years previously written an _opera bouffe_ entitled _L'Etoile_, which was performed at the Bouffes Parisiens. In 1881 he was appointed chorus-master of the concerts then recently established by Lamoureux. In 1883 he composed the brilliant orchestral rhapsody entitled _Espana_, the themes of which he had jotted down when travelling in Spain. His opera _Gwendoline_ was brought out with considerable success at Brussels on the 10th of April 1886, and was given later at the Paris Grand Opera. The following year 1887, _Le Roi malgre lui_, an opera of a lighter description, was produced in Paris at the Opera Comique, its run being interrupted by the terrible fire by which this theatre was destroyed. His last opera, _Briseis_, was left unfinished, and performed in a fragmentary condition at the Paris Opera, after the composer's death in Paris on the 13th of September 1894. Chabrier was also the author of a set of piano pieces entitled _Pieces pittoresques, Valses romantiques_, for two pianos, a fantasia for horn and piano, &c. His great admiration for Wagner asserted itself in _Gwendoline_, a work which, in spite of inequalities due to want of experience, is animated by a high artistic ideal, is poetically conceived, and shows considerable harmonic originality, besides a thorough mastery over the treatment of the orchestra. The characteristics of _Le Roi malgre lui_ have been well summed up by M. Joncieres when he alludes to "cette verve inepuisable, ces rythmes endiables, cette exuberance de gaiete et de vigueur, a laquelle venait se joindre la note melancolique et emue." Chabrier's premature death prevented him from giving the full measure of his worth.

CHACMA, the Hottentot name of the Cape baboon, _Papio porcarius_, a species inhabiting the mountains of South Africa as far north as the Zambezi. Of the approximate size of an English mastiff, this powerful baboon is blackish grey in colour with a tinge of green due to the yellow rings on most of the hairs. Unlike most of its tribe, it is a good climber; and where wooded cliffs are not available, will take up its quarters in tall trees. Chacmas frequently strip orchards and fruit-gardens, break and devour ostrich eggs, and kill lambs and kids for the sake of the milk in their stomachs.

CHACO, a territory of northern Argentina, part of a large district known as the Gran Chaco, bounded N. by the territory of Formosa, E. by Paraguay and Corrientes, S. by Santa Fe, and W. by Santiago del Estero and Salta. The Bermejo river forms its northern boundary, and the Paraguay and Parana rivers its eastern; these rivers are its only means of communication. Pop. (1895) 10,422; (1904, est.) 13,937; area, 52,741 sq. m. The northern part consists of a vast plain filled with numberless lagoons; the southern part is slightly higher and is covered with dense forests, occasionally broken by open grassy spaces. Its forests contain many species of trees of great economic value; among them is the _quebracho_, which is exported for the tannin which it contains. The capital, Resistencia, with an estimated population of 3500 in 1904, is situated on the Parana river opposite the city of Corrientes. There is railway communication between Santa Fe and La Sabana, an insignificant timber-cutting village on the southern frontier. In the territory there are still several tribes of uncivilized Indians, who occasionally raid the neighbouring settlements of Santa Fe.

CHACONNE (Span. _chacona_), a slow dance, introduced into Spain by the Moors, now obsolete. It resembles the Passacaglia. The word is used also of the music composed for this dance--a slow stately movement in 3/4 time. Such a movement was often introduced into a sonata, and formed the conventional finale to an opera or ballet until the time of Gluck.

CHAD [CEADDA], SAINT (d. 672), brother of Cedd, whom he succeeded as abbot at Lastingham, was consecrated bishop of the Northumbrians by Wine, the West Saxon bishop, at the request of Oswio in 664. On the return of Wilfrid from France, where he had been sent to be consecrated to the same see, a dispute of course arose, which was settled by Theodore in favour of Wilfrid after three years had passed. Chad thereupon retired to Lastingham, whence with the permission of Oswio he was summoned by Wulfhere of Mercia to succeed his bishop Jaruman, who died 667. Chad built a monastery at Barrow in Lincolnshire and fixed his see at Lichfield. He died after he had held his bishopric in Mercia two and a half years, and was succeeded by Wynfrith. Bede gives a beautiful character of Chad.

See Bede's _Hist. Eccl._ edited by C. Plummer, iii. 23, 24, 28; iv. 2, 3 (Oxford, 1896); Eddius, _Vita Wilfridi_, xiv., xv. edited by J. Raine, Rolls Series (London, 1879).

CHAD, a lake of northern Central Africa lying between 12 deg. 50' and 14 deg. 10' N. and 13 deg. and 15 deg. E. The lake is situated about 850 ft. above the sea in the borderland between the fertile and wooded regions of the Sudan on the south and the arid steppes which merge into the Sahara on the north. The area of the lake is shrinking owing to the progressive desiccation of the country, Saharan climate and conditions replacing those of the Sudan. The drying-up process has been comparatively rapid since the middle of the 19th century, a town which in 1850 was on the southern margin of the lake being in 1905 over 20 m. from it. On the west the shore is perfectly flat, so that a slight rise in the water causes the inundation of a considerable area--a fact not without its influence on the estimates made at varying periods as to the size of the lake. Around the north-west and north shores is a continuous chain of gently sloping sand-hills covered with bush. This region abounds in big game and birds are plentiful. In the east, the country of Kanem, the desiccation has been most marked. Along this coast is a continuous chain of islands running from north-west to south-east. But what were islands when viewed by Overweg in 1851, formed in 1903 part of the mainland and new islands had arisen in the lake. They are generally low, being composed of sand and clay, and lie from 5 to 20 m. from the shore, which throughout its eastern side nowhere faces open water. The channels between the islands do not exceed 2 m. in width. Two principal groups are distinguished, the Kuri archipelago in the south, and the Buduma in the north. The inhabitants of the last-named islands were noted pirates until reduced to order by the French. The coast-line is, in general, undefined and marshy, and broken into numerous bays and peninsulas. It is also, especially on the east, lined by lagoons which communicate with the lake by intricate channels. The lake is nowhere of great depth, and about midway numerous mud-banks, marshes, islands and dense growths of aqueous plants stretch across its surface. Another stretch of marsh usually cuts off the northernmost part of the lake from the central sections. The open water varies in depth from 3 ft. in the north-west to over 20 in the south, where desiccation is less apparent. Fed by the Shari (q.v.) and other rivers, the lake has no outlet and its area varies according to the season. The flood water brought down by the Shari in December and January causes the lake to rise to a maximum of 24 ft., the water spreading over low-lying ground, left dry again in May or June. But after several seasons of heavy rainfall the waters have remained for years beyond their low-water level. Nevertheless the secular shrinking goes on, the loss by evaporation and percolation exceeding the amount of water received; whilst, on the average, the rainfall is diminishing. In 1870 the lake rose to an exceptional height, but since then, save in 1897, there has been only the normal seasonal rise. The prevalent north-east wind causes at times a heavy swell on the lake. Fish abound in its waters, which are sweet, save at low-level, when they become brackish. The lagoons are believed to act as purifying pans in which the greater part of the salt in the water is precipitated. In the south-west end of the lake the water is yellow, caused by banks of clay; elsewhere it is clear.

[Illustration: Lake Chad]

The southern basin of Chad is described under the Shari, which empties its waters into the lake about the middle of the southern shore, forming a delta of considerable extent. Beyond the south-east corner of the lake is a depression known as the Bahr-el-Ghazal (not to be confounded with the Nile affluent of the same name). This depression is the termination of what is in all probability the bed of one of the dried-up Saharan rivers. Coming from the Tibesti highlands the Bahr-el-Ghazal has a south-westerly trend to Lake Chad. Near the lake the valley was formerly swampy, and at high-water the lake overflowed into it. There was also at one time communication between the Shari and the Bahr-el-Ghazal, so that the water of the first-named stream reached Chad by way of the Bahr-el-Ghazal. There is now neither inlet nor outlet to the lake in this direction, the mouth of the Ghazal having become a fertile millet field. There is still, however, a distinct current from the Shari delta to the east end of the lake--known to the natives, like the depression beyond, as the Bahr-el-Ghazal--indicative of the former overflow outlet.

Besides the Shari, the only important stream entering Lake Chad is the Waube or Yo (otherwise the Komadugu Yobe), which rises near Kano, and flowing eastward enters the lake on its western side 40 m. north of Kuka. In the rains the Waube carries down a considerable body of water to the lake.

Lake Chad is supposed to have been known by report to Ptolemy, and is identified by some writers with the Kura lake of the middle ages. It was first seen by white men in 1823 when it was reached by way of Tripoli by the British expedition under Dr Walter Oudney, R.N., the other members being Captain Hugh Clapperton and Major (afterwards Lieut.-Colonel) Dixon Denham. By them the lake was named Waterloo. In 1850 James Richardson, accompanied by Heinrich Barth and Adolf Overweg, reached the lake, also via Tripoli, and Overweg was the first European to navigate its waters (1851). The lake was visited by Eduard Vogel (1855) and by Gustav Nachtigal (1870), the last-named investigating its hydrography in some detail. In 1890-1893 its shores were divided by treaty between Great Britain, France and Germany. The first of these nations to make good its footing in the region was France. A small steamer, brought from the Congo by Emile Gentil, was in 1897 launched on the Shari, and reaching the Chad, navigated the southern part of the lake. Communication between Algeria and Lake Chad by way of the Sahara was opened, after repeated failures, by the French explorer F. Foureau in 1899-1900. At the same time a French officer, Lieut. Joalland, reached the lake from the middle Niger, continuing his journey round the north end to Kanem. A British force under Colonel T.L.N. Morland visited the lake at the beginning of 1902, and in May of the same year the Germans first reached it from Cameroon. In 1902-1903 French officers under Colonel Destenave made detailed surveys of the south-eastern and eastern shores and the adjacent islands. In 1903 Captain E. Lenfant, also a French officer, succeeded in reaching the lake (which he circumnavigated) via the Benue, proving the existence of water communication between the Shari and the Niger. In 1905 Lieut. Boyd Alexander, a British officer, further explored the lake, which then contained few stretches of open water. The lake is bordered W. and S.W. by Bornu, which is partly in the British protectorate of Nigeria and

## partly in the German protectorate of Cameroon. Bagirmi to the S.E. of

the lake and Kanem to the N.E. are both French possessions. The north and north-west shores also belong to France. One of the ancient trade routes across the Sahara--that from Tripoli to Kuka in Bornu--strikes the lake at its north-west corner, but this has lost much of its former importance.

See the works of Denham, Clapperton, Barth and Nachtigal cited in the biographical notices; _Geog. Journal_, vol. xxiv. (1904); Capt. Tilho in _La Geographie_ (March 1906); Boyd Alexander, _From the Niger to the Nile_, vol. i. (London, 1907); A. Chevalier, _Mission Chari-Lac Tchad 1902-1904_ (Paris 1908); E. Lenfant, _La Grande Route du Tchad_ (Paris, 1905); H. Freydenberg, _Etude sur le Tchad et le bassin du Chari_ (Paris, 1908).

CHADDERTON, an urban district of Lancashire, England, within the parliamentary borough of Oldham (q.v.). Pop. (1901) 24,892. Cotton and chemical works, and the coal-mines of the neighbourhood, employ the large industrial population.

CHADERTON, LAURENCE (?1536-1640), Puritan divine, was born at Lees Hall, in the parish of Oldham, Lancashire, probably in September 1536, being the second son of Edmund Chaderton, a gentleman of an ancient and wealthy family, and a zealous Catholic. Under the tuition of Laurence Vaux, a priest, he became an able scholar. In 1564 he entered Christ's College, Cambridge, where, after a short time, he formally adopted the reformed doctrines and was in consequence disinherited by his father. In 1567 he was elected a fellow of his college, and subsequently was chosen lecturer of St Clement's church, Cambridge, where he preached to admiring audiences for many years. He was a man of moderate views, though numbering among his friends extremists like Cartwright and Perkins. So great was his reputation that when Sir Walter Mildmay founded Emmanuel College in 1584 he chose Chaderton for the first master, and on his expressing some reluctance, declared that if he would not accept the office the foundation should not go on. In 1604 Chaderton was appointed one of the four divines for managing the cause of the Puritans at the Hampton Court conference; and he was also one of the translators of the Bible. In 1578 he had taken the degree of B.D., and in 1613 he was created D.D. At this period he made provision for twelve fellows and above forty scholars in Emmanuel College. Fearing that he might have a successor who held Arminian doctrines, he resigned the mastership in favour of John Preston, but survived him, and lived also to see the college presided over successively by William Sancroft (or Sandcroft) and Richard Holdsworth. He died on the 13th of November 1640 at the age of about 103, preserving his bodily and mental faculties to the end.

Chaderton published a sermon preached at St Paul's Cross about 1580, and a treatise of his _On Justification_ was printed by Anthony Thysius, professor of divinity at Leiden. Some other works by him on theological subjects remain in manuscript.

CHADWICK, SIR EDWIN (1800-1890), English sanitary reformer, was born at Longsight, near Manchester, on the 24th of January 1800. Called to the bar without any independent means, he sought to support himself by literary work, and his essays in the _Westminster Review_ (mainly on different methods of applying scientific knowledge to the business of government) introduced him to the notice of Jeremy Bentham, who engaged him as a literary assistant and left him a handsome legacy. In 1832 he was employed by the royal commission appointed to inquire into the operation of the poor laws, and in 1833 he was made a full member of that body. In conjunction with Nassau W. Senior he drafted the celebrated report of 1834 which procured the reform of the old poor law. His special contribution was the institution of the union as the area of administration. He favoured, however, a much more centralized system of administration than was adopted, and he never ceased to complain that the reform of 1834 was fatally marred by the rejection of his views, which contemplated the management of poor-law relief by salaried officers controlled from a central board, the boards of guardians acting merely as inspectors. In 1834 he was appointed secretary to the poor law commissioners. Finding himself unable to administer in accordance with his own views an act of which he was largely the author, his relations with his official chiefs became much strained, and the disagreement led, among other causes, to the dissolution of the poor law commission in 1846. Chadwick's chief contribution to political controversy was his constant advocacy of entrusting certain departments of local affairs to trained and selected experts, instead of to representatives elected on the principle of local self-government. While still officially connected with the poor law he had taken up the question of sanitation in conjunction with Dr Southwood Smith, and their joint labours produced a most salutary improvement in the public health. His report on "The Sanitary Condition of the Labouring Population" (1842) is a valuable historical document. He was a commissioner of the Board of Health from its establishment in 1848 to its abolition in 1854, when he retired upon a pension, and occupied the remainder of his life in voluntary contributions to sanitary and economical questions. He died at East Sheen, Surrey, on the 6th of July 1890. He had been made K.C.B. in 1889.

See a volume on _The Evils of Disunity in Central and Local Administration ... and the New Centralization for the People_, by Edwin Chadwick (1885); also _The Health of Nations, a Review of the Works of Edwin Chadwick, with a Biographical Introduction_, by Sir B. W. Richardson (1887).

CHAEREMON, Athenian dramatist of the first half of the 4th century B.C. He is generally considered a tragic poet. Aristotle (_Rhetoric_, iii. 12) says his works were intended for reading, not for representation. According to Suidas, he was also a comic poet, and the title of at least one of his plays (_Achilles Slayer of Thersites_) seems to indicate that it was a satyric drama. His _Centaurus_ is described by Aristotle (_Poet._ i. 12) as a rhapsody in all kinds of metres. The fragments of Chaeremon are distinguished by correctness of form and facility of rhythm, but marred by a florid and affected style reminiscent of Agathon. He especially excelled in descriptions (irrelevantly introduced) dealing with such subjects as flowers and female beauty. It is not agreed whether he is the author of three epigrams in the Greek Anthology (Palatine vii. 469, 720, 721) which bear his name.

See H. Bartsch, _De Chaeremone Poeta tragico_ (1843); fragments in A. Nauck, _Fragmenta Tragicorum Graecorum_.

CHAEREMON, of Alexandria (1st century A.D.), Stoic philosopher and grammarian. He was superintendent of the portion of the Alexandrian library that was kept in the temple of Serapis, and as custodian and expounder of the sacred books ([Greek: ierogrammateus] sacred scribe) belonged to the higher ranks of the priesthood. In A.D. 49 he was summoned to Rome, with Alexander of Aegae, to become tutor to the youthful Nero. He was the author of a _History of Egypt_; of works on _Comets, Egyptian Astrology_, and _Hieroglyphics_; and of a grammatical treatise on _Expletive Conjunctions_ ([Greek: syndesmoi parapleropaeromatikoi]). Chaeremon was the chief of the party which explained the Egyptian religious system as a mere allegory of the worship of nature. His books were not intended to represent the ideas of his Egyptian contemporaries; their chief object was to give a description of the sanctity and symbolical secrets of ancient Egypt. He can hardly be identical with the Chaeremon who accompanied (c. 26 B.C.; Strabo xvii. p. 806) Aelius Gallus, praefect of Egypt, on a journey into the interior of the country.

Fragments in C. Muller, _Fragmenta Historicorum Graecorum_, iii. 495-499.

CHAERONEIA, or CHAERONEA, an ancient town of Boeotia, said by some to be the Homeric Arne, situated about 7 m. W. of Orchomenus. Until the 4th century B.C. it was a dependency of Orchomenus, and at all times it played but a subordinate part in Boeotian politics. Its importance lay in its strategic position near the head of the defile which presents the last serious obstacle to an invader in central Greece. Two great battles were fought on this site in antiquity. In 338 B.C. Philip II. and Alexander of Macedon were confronted by a confederate host from central Greece and Peloponnese under the leadership of Thebes and Athens, which here made the last stand on behalf of Greek liberty. A hard-fought conflict, in which the Greek infantry displayed admirable firmness, was decided in favour of Philip through the superior organization of his army. In 86 B.C. the Roman general L. Cornelius Sulla defeated the army of Mithradates VI., king of Pontus, near Chaeroneia. The latter's enormous numerical superiority was neutralized by Sulla's judicious choice of ground and the steadiness of his legionaries; the Asiatics after the failure of their attack were worn down and almost annihilated. Chaeroneia is also notable as the birthplace of Plutarch, who returned to his native town in old age, and was held in honour by its citizens for many successive generations. Pausanias (ix. 40) mentions the divine honours accorded at Chaeroneia to the sceptre of Agamemnon, the work of Hephaestus (cf. _Iliad_, ii. 101). The site of the town is partly occupied by the village of Kapraena; the ancient citadel was known as the Petrachus, and there is a theatre cut in the rock. A colossal seated lion a little to the S.E. of the site marks the grave of the Boeotians who fell fighting against Philip; this lion was found broken to pieces; the tradition that it was blown up by Odysseus Androutsos is incorrect (see Murray, _Handbook for Greece_, ed. 5, 1884, p. 409). It has now been restored and re-erected (1905).

AUTHORITIES.--Thucydides iv. 76; Diodorus xvi. 85-86; Plutarch, _Alexander_, ch. 9; _Sulla_, chs. 16-19; Appian, _Mithradatica_, chs. 42-45; W.M. Leake, _Travels in Northern Greece_ (London, 1835), ii. 112-117, 192-201; B.V. Head, _Historia Numorum_ (Oxford, 1887), p. 292; J. Kromayer, _Antike Schlachtfelder in Griechenland_ (Berlin, 1903), pp. 127-195; G. Sotiriades in _Athen. Mitteil._ 1903, pp. 301 ff.; 1905, p. 120; 1906, p. 396; [Greek: Ephem. Archaiol.], 1908, p. 65.

CHAETOGNATHA, the name given by R. Leuckhart to a small group of transparent and for the most part pelagic organisms, whose position in the animal kingdom is a very isolated one. Only three genera, _Sagitta_, _Spadella_ and _Krohnia_, are recognised, and the number of species is small. Nevertheless these animals exist in extraordinary quantities, so that at certain seasons and under certain conditions the surface of the sea seems almost stiff with the incredible multitude of organisms which pervade it. Rough seas, &c., cause them to seek safety in dropping into deeper water. Deep-sea forms also occur, but in spite of this the group is essentially pelagic.

[Illustration: _Spadella cephaloptera_ (Busch).

St, Septa dividing body-cavity transversely. g^2, Cerebral ganglia. n^1, Commissure uniting this with ventral ganglion (not shown in fig.). n^2, Nerve uniting cerebral ganglia with small ganglia on head. nr, Olfactory nerve. d, Alimentary canal. r, Olfactory organ. te, Tentacle. t, Tactile hairs springing from surface of body. e, Ovary. el, Oviduct. ho, Testes. sg, Vas deferens. f^2, f^3, Lateral and caudal fins. sb, Seminal pouch.

The eyes are indicated as black dots behind the cerebral ganglia.]

As a rule the body is some 1 to 2 or 3 cm. in length, though some species are larger, by 4 or 5 mm. in breadth, and it is shaped something like a torpedo with side flanges and a slightly swollen, rounded head. It can be divided into three regions--(i.) head, (ii.) trunk, and (iii.) tail, separated from one another by two transverse septa. The almost spherical head is covered by a hood which can be retracted; it bears upon its side a number of sickle-shaped, chitinous hooks and one or more short rows of low spines--both of these features are used in characterizing the various species. A pair of eyes lie dorsally and behind them is a closed circlet, often pulled out into various shapes, of modified epidermis, to which an olfactory function has been attributed. The interior of the head is filled up with masses of muscle fibres which are mainly occupied with moving the sickle-shaped hooks. The trunk contains a spacious body-cavity filled during the breeding season by the swollen ovaries, and the same is true of the tail if we substitute testes for ovaries.

The skin consists of a transparent cuticle excreted by the underlying ectoderm, the cells of which though usually one-layered may be heaped up into several layers in the head; beneath this is a basement membrane, and then a layer of longitudinal muscle fibres which are limited inside by a layer of peritoneal cells. The muscles are striated and arranged in four quadrants, two dorso-lateral and two ventro-lateral, an arrangement which recalls that of the Nematoda, whilst in their histology they somewhat resemble the muscles of the Oligochaeta. Along each side of the body stretches a horizontal fin and a similar flange surrounds the tail. Into these fins, which are largely cuticular and strengthened by radiating bars, a single layer of ectoderm cells projects.

The mouth, a longitudinal slit, opens on to the ventral surface of the head. It leads into a straight alimentary canal whose walls consist of a layer of ciliated cells ensheathed in a thin layer of peritoneal cells. There is no armature, and no glands, and the whole tract can only be divided into an oesophagus and an intestine. The latter runs with no twists or coils straight to the anus, which is situated at the junction of the trunk with the tail. A median mesentery running dorso-ventrally supports the alimentary canal and is continued behind it into the tail, thus dividing the body cavity into two lateral halves.

There are no specialized circulatory, respiratory or excretory organs.

The nervous system consists of a cerebral ganglion in the head, a conspicuous ventral ganglion in the trunk, and of lateral commissures uniting these ganglia on each side. The whole of this system has retained its primitive connexion with the ectoderm. The cerebral ganglion also gives off a nerve on each side to a pair of small-ganglia, united by a median commissure, which have sunk into and control the muscles of the head. As in other animals there is a minute but extensive nervous plexus, which permeates the whole body and takes its origin from the chief ganglia. In addition to the eyes and the olfactory circle on the head scattered tactile papillae are found on the ectoderm.

Chaetognatha are hermaphrodite. The ovaries are attached to the side walls of the trunk region; between them and the body wall lie the two oviducts whose inner and anterior end is described as closed, their outer ends opening one on each side of the anus, where the trunk joins the tail. According to Miss N.M. Stevens the so-called oviduct acts only as a "sperm-duct" or receptaculum seminis. The spermatozoa enter it and pass through its walls and traverse a minute duct formed of two accessory cells, and finally enter the ripe ovum. Temporary oviducts are formed between the "sperm-duct" and the germinal epithelium at each oviposition. A number of ova ripen simultaneously. The two testes lie in the tail and are formed by lateral proliferations of the living peritoneal cells. These break off and, lying in the coelomic fluid, break up into spermatozoa. They pass out through short vasa deferentia with internal ciliated funnels, sometimes an enlargement on their course--the seminal vesicles--and a minute external pore situated on the side of the tail.

With hardly an exception the transparent eggs are laid into the sea and float on its surface. The development is direct and there is no larval stage. The segmentation is complete; one side of the hollow blastosphere invaginates and forms a gastrula. The blastopore closes, a new mouth and a new anus subsequently arising. The archenteron gives off two lateral pounchs and thus becomes trilobed. The middle lobe forms the alimentary canal; it closes behind and opens to the exterior anteriorly and so makes the mouth. The two lateral lobes contain the coelom; each separates off in front a segment which forms the head and presumably then divides again to form anteriorly the trunk, and posteriorly the tail regions. An interesting feature of the development of Chaetognaths is that, as in some insects, the cells destined to form the reproductive organs are differentiated at a very early period, being apparent even in the gastrula stage.

The great bulk of the group is pelagic, as the transparent nature of all their tissues indicates. They move by flexing their bodies. _Spadella cephaloptera_ is, however, littoral and oviposits on seaweed, and the "Valdivia" brought home a deep-sea species.

The three genera are differentiated as follows:--

_Sagitta_ M. Slabber, with two pairs of lateral fins. This genus was named as long ago as 1775.

_Krohnia_ P. Langerhans, with one lateral fin on each side, extending on to the tail.

_Spadella_ P. Langerhans, with a pair of lateral fins on the tail and a thickened ectodermic ridge running back on each side from the head to the anterior end of the fin.

The group is an isolated one and should probably be regarded as a separate phylum. It has certain histological resemblances with the Nematoda and certain primitive Annelids, but little stress must be laid on these. The most that can be said is that the Chaetognaths begin life with three segments, a feature they share with such widely-differing groups as the Brachiopoda, the Echinoderma and the Enteropneusta, and probably Vertebrata generally.

See O. Hertwig, _Die Chaetognathen, eine Monographie_ (Jena, 1880); B.J. Grassi, _Chetognathi: Flora u. Fauna d. Golfes von Neapel_ (1883); S. Strodtman, _Arch. Naturg._ lviii., 1892; N.M. Stevens, _Zool. Jahrb. Anat._ xviii., 1903, and xxi., 1905. (A. E. S.)

CHAETOPODA (Gr. [Greek: chaite], hair, [Greek: pous], foot), a zoological class, including the majority of the Annelida (q.v.), and indeed, save for the Echiuroidea (q.v.), co-extensive with that group as usually accepted. They are divisible into the Haplodrili (q.v.) or Archiannelida, the Polychaeta containing the marine worms, the Oligochaeta or terrestrial and fresh-water annelids (see EARTHWORM), the Hirudinea or leeches (see LEECH), and a small group of parasitic worms, the Myzostomida (q.v.).

The distinctive characters of the class Chaetopoda as a whole are partly embodied in the name. They possess (save for certain Archiannelida, most Hirudinea, and other very rare exceptions) setae or chaetae implanted in epidermal pits. The setae are implanted metamerically in accordance with the metamerism of the body, which consists of a prostomium followed by a number of segments. The number of segments in an individual is frequently more or less definite. The anterior end of body always shows some "cephalization." The internal organs are largely repeated metamerically, in correspondence with the external metamerism. Thus the body cavity is divided into a sequence of chambers by transverse septa; and even among the Hirudinea, where this condition is usually not to be observed, there is embryological evidence that the existing state of affairs is derived from this. Commonly the nephridia are strictly paired a single pair to each segment, while the branches of the blood vascular system are similarly metameric. The alimentary canal is nearly always a straight tube running from the mouth, which is surrounded by the first segment of the body and overhung by the prostomium, to the anus, which is then either surrounded by the last segment of the body or opens dorsally a little way in front of this.

THE CLASS AS A WHOLE.--The Chaetopoda are with but few exceptions (Myzostomida in part, _Sternaspis_) elongated worms, flattened or, more usually, cylindrical, and bilaterally symmetrical. The body consists of a number of exactly similar or closely similar segments, which are never fused and metamorphosed, as in the Arthropoda, to form specialized regions of the body. It is, however, always possible to recognize a head, which consists at least of the peristomial segment with a forward projection of the same, the prostomium. A thorax also is sometimes to be distinguished from an abdomen. Where locomotive appendages (the parapodia of the Polychaeta) exist, they are never jointed, as always in the Arthropoda; nor are they modified anteriorly to form jaws, as in that group.

[Illustration: FIG 1.--A, side view of the head region of _Nereis cultrifera_; B, dorsal view of the same.

E, Eye. M, Mouth. d.c, Dorcal cirrus. per, Peristomium, probably equal to two segments, per.c, Peristomial cirri. pl, Prostomial palp. pp, Parapodium. pr, Prostomium. pr.t, Prostomial tentacle. t.s, Trunk segment. v.c, Ventral cirrus.]

The prostomium overhangs the mouth, and is often of considerable size and, as a rule, quite distinct from the segment following, being separated by an external groove, and containing, at least temporarily, the brain, which always arises there. Its cavity also is at first independent of the coelom though later invaded by the latter. In any case the cavity of the prostomium is single, and not formed, as is the cavity of the segments of the body, by paired coelomic chambers. It has, however, been alleged that this cavity is formed by a pair of mesoblastic somites (N. Kleinenberg), in which case there is more reason for favouring the view that would assign an equality between the prostomium and the (in that case) other segments of the body. The peculiar prostomium of _Tomopteris_ is described below. The body wall of the Chaetopoda consists of a "dermo-muscular" tube which is separated from the gut by the coelom and its peritoneal walls, except in most leeches. A single layer of epidermic cells, some of which are glandular, forms the outer layer. Rarely are these ciliated, and then only in limited tracts. They secrete a cuticle which never approaches in thickness the often calcified cuticle of Arthropods. Below this is a circular, and below that again a longitudinal, layer of muscle fibres. These muscles are not striated, as they are in the Arthropoda.

_Setae_.--These chitinous, rod-like, rarely squat and then hook-like structures are found in the majority of the Chaetopoda, being absent only in certain Archiannelida, most leeches, and a very few Oligochaeta. They exist in the Brachiopoda (which are probably not unrelated to the Chaetopoda), but otherwise are absolutely distinctive of the Chaetopods. The setae are invariably formed each within an epidermic cell, and they are sheathed in involutions of the epidermis. Their shape and size varies greatly and is often of use in classification. The setae are organs of locomotion, though their large size and occasionally jagged edges in some of the Polychaeta suggest an aggressive function. They are disposed in two groups on either side, corresponding in the Polychaeta to the parapodia; the two bundles are commonly reduced among the earthworms to two pairs of setae or even to a single seta. On the other hand, in certain Polychaeta the bundles of setae are so extensive that they nearly form a complete circle surrounding the body; and in the Oligochaet genus _Perichaeta_ (= _Pheretima_), and some allies, there is actually a complete circle of setae in each segment broken only by minute gaps, one dorsal, the other ventral.

_Coelom_.--The Chaetopoda are characterized by a spacious coelom, which is divided into a series of chambers in accordance with the general metamerism of the body. This is the typical arrangement, which is exhibited in the majority of the Polychaeta and Oligochaeta; in these the successive chambers of the coelom are separated by the intersegmental septa, sheets of muscle fibres extending from the body wall to the gut and thus forming partitions across the body. The successive cavities are not, however, completely closed from each other; there is some communication between adjoining segments, and the septa are sometimes deficient here and there. Thus in the Chaetopoda the perivisceral cavity is coelomic; in this respect the group contrasts with the Arthropoda and Molluscs, where the perivisceral cavity is, mainly at least, part of the vascular or haemal system, and agrees with the Vertebrata. The coelom is lined throughout by cells, which upon the intestine become large and loaded with excretory granules, and are known as chloragogen cells. Several forms of cells float freely in the fluid of the coelom. In another sense also the coelom is not a closed cavity, for it communicates in several ways with the external medium. Thus, among the Oligochaeta there are often a series of dorsal pores, or a single head pore, present also among the Polychaeta (in _Ammochares_). In these and other Chaetopods the coelom is also put into indirect relations with the outside world by the nephridia and by the gonad ducts. In these features, and in the fact that the gonads are local proliferations of the coelomic epithelium, which have undergone no further changes in the simpler forms, the coelom of this group shows in a particularly clear fashion the general characters of the coelom in the higher Metazoa. It has been indeed largely upon the conditions characterizing the Chaetopoda that the conception of the coelom in the Coelomocoela has been based.

Among the simpler Chaetopoda the coelom retains the character of a series of paired chambers, showing the above relations to the exterior and to the gonads. There are, however, further complications in some forms. Especially are these to be seen in the more modified Oligochaeta and in the much more modified Hirudinea. In the Polychaeta, which are to be regarded as structurally simpler forms than the two groups just referred to, there is but little subdivision of the coelom of the segments, indeed a tendency in the reverse direction, owing to the suppression of septa. Among the Oligochaeta the dorsal vessel in _Dinodrilus_ and _Megascolides_ is enclosed in a separate coelomic chamber which may or may not communicate with the main coelomic cavity. To this pericardial coelom is frequently added a gonocoel enclosing the gonads and the funnels of their ducts. This condition is more fully dealt with below in the description of the Oligochaeta. The division and, indeed, partial suppression of the coelom culminates in the leeches, which in this, as in some other respects, are the most modified of Annelids.

_Nervous System._--In all Chaetopods this system consists of cerebral ganglia connected by a circumoesophageal commissure with a ventral ganglionated cord. The plan of the central nervous system is therefore that of the Arthropoda. Among the Archiannelida, in _Aeolosoma_ and some Polychaetes, the whole central nervous system remains imbedded in the epidermis. In others, it lies in the coelom, often surrounded by a special and occasionally rather thick sheath. The cerebral ganglia constitute an archicerebrum for the most part, there being no evidence that, as in the Arthropoda, a movement forward of post-oral ganglia has taken place. In the leeches, however, there seems to be the commencement of the formation of a syncerebrum. In the latter, the segmentally arranged ganglia are more sharply marked off from the connectives than in other Chaetopods, where nerve cells exist along the whole ventral chain, though more numerous in segmentally disposed swellings.

_Vascular System._--In addition to the coelom, another system of fluid-holding spaces lies between the body wall and the gut in the Chaetopoda. This is the vascular or haemal system (formerly and unnecessarily termed pseudhaemal). With a few exceptions among the Polychaeta the vascular system is always present among the Chaetopoda, and always consists of a system of vessels with definite walls, which rarely communicate with the coelom. It is in fact typically a closed system. The larger trunks open into each other either directly by cross branches, or a capillary system is formed. There are no lacunar blood spaces with ill-defined or absent walls except for a sinus surrounding the intestine, which is at least frequently present. The principal trunks consist of a dorsal vessel lying above the gut, and a ventral vessel below the gut but above the nervous cord. These two vessels in the Oligochaeta are united in the anterior region of the body by a smaller or greater number of branches which surround the oesophagus and are, some of them at least, contractile and in that case wider than the rest. The dorsal vessel also communicates with the ventral vessel indirectly by the intestinal sinus, which gives off branches to both the longitudinal trunks, and by tegementary vessels and capillaries which supply the skin and the nephridia. In the smaller and simpler forms the capillary networks are much reduced, but the dorsal and ventral vessels are usually present. The former, however, is frequently developed only in the anterior region of the body where it emerges from the peri-intestinal blood sinus. On the other hand, additional longitudinal trunks are sometimes developed, the chief one of which is a supra-intestinal vessel lying below the dorsal vessel and closely adherent to the walls of the oesophagus in which region it appears. The capillaries sometimes (in many leeches and Oligochaeta) extend into the epidermis itself. Usually they do not extend outwards of the muscular layers of the body wall. The main trunks of the vascular system often possess valves at the origin of branches which regulate the direction of the blood flow. Among many Oligochaeta the dorsal blood-vessel is partly or entirely a double tube, which is a retention of a character shown by F. Vezhdovsky to exist in the embryo of certain forms. The blood in the Chaetopoda consists of a plasma in which float a few corpuscles. The plasma is coloured red by haemoglobin: it is sometimes (in _Sabella_ and a few other Polychaeta) green, which tint is due to another respiratory pigment. The plasma may be pink (_Magelona_) or yellow (_Aphrodite_) in which cases the colour is owing to another pigment. In _Aeolosoma_ it is usually colourless. The vascular system is in the majority of Chaetopods a closed system. It has been asserted (and denied) that the cellular rod which is known as the "Heart-body" (_Herzkorper_), and is to be found in the dorsal vessel of many Oligochaeta and Polychaeta, is formed of cells which are continuous with the chloragogen cells, thus implying the existence of apertures of communication with the coelom. The statement has been often made and denied, but it now seems to have been placed on a firm basis (E.S. Goodrich), that among the Hirudinea the coelom, which is largely broken up into narrow tubes, may be confluent with the tubes of the vascular system. This state of affairs has no antecedent improbability about it, since in the Vertebrata the coelom is unquestionably confluent with the haemal system through the lymphatic vessels. Finally, there are certain Polychaeta, _e g._ the _Capitellidae_, in which the vascular system has vanished altogether, leaving a coelom containing haemoglobin-impregnated corpuscles. It has been suggested (E. Ray Lankester) that this condition has been arrived at through some such intermediate stage as that offered by Polychaet _Magelona_. In this worm the ventral blood-vessel is so swollen as to occupy nearly the whole of the available coelom. Carry the process but a little farther and the coelom disappears and its place is taken by a blood space or haemocoel. It has been held that the condition shown in certain leeches tend to prove that the coelom and haemocoel are primitively one series of spaces which have been gradually differentiated. The facts of development, however, prove their distinctness, though those same facts do not speak clearly as to the true nature of the blood system. One view of the origin of the latter (largely based upon observations upon the development of _Polygordius_) sees in the blood system a persistent blastocoel. F. Vezhdovsky has lately seen reasons for regarding the blood system as originating entirely from the hypoblast by the secretion of fluid, the blood, from particular intestinal cells and the consequent formation of spaces through pressure, which become lined with these cells.

_Nephridia and Coelomoducts_.--The name "Nephridium" was originally given by Sir E. Ray Lankester to the members of a series of tubes, proved in some cases to be excretory in nature, which exist typically to the number of a single pair in most of the segments of the Chaetopod body, and open each by a ciliated orifice into the coelom on the one hand, and by a pore on to the exterior of the body on the other. In its earlier conception, this view embraced as homologous organs (so far as the present group is concerned) not only the nephridia of Oligochaeta and Hirudinea, which are obviously closely similar, but the wide tubes with an intercellular lumen and large funnels of certain Polychaeta, and (though with less assurance) the gonad ducts in Oligochaeta and Hirudinea. The function of nitrogenous excretion was not therefore a necessary part of the view--though it may be pointed out that there are grounds for believing that the gonad ducts are to some extent also organs of excretion (see below). Later, the investigations of E. Meyer and E.S. Goodrich, endorsed by Lankester, led to the opinion that under the general morphological conception of "nephridium" were included two distinct sets of organs, viz. nephridia and coelomoducts. The former (represented by, e.g. the "segmental organs" of _Lumbricus_) have been asserted to be "ultimately, though not always, actually traceable to the ectoderm"; the latter (represented by, e.g. the oviduct of _Lumbricus_) are parts of the coelomic wall itself, which have grown out to the exterior. The nephridia, in fact, on this view, are _ectodermic ingrowths_, the coelomoducts _coelomic outgrowths_. The cavity of the former has nothing to do with coelom. The cavity of the latter is coelom.

The embryological facts upon which this view has been based, however, have been differently interpreted. According to C.O. Whitman the entire nephridial system (in the leech _Clepsine_) is formed by the differentiation of a continuous epiblastic band on each side. The exact opposite is maintained by R.S. Bergh (for _Lumbricus_ and _Criodrilus_), whose figures show a derivation of the entire nephridium from mesoblast, and an absence of any connexion between successive nephridia by any continuous band, epiblastic or mesoblastic. A midway position is taken up by Wilson, who asserts the mesoblastic formation of the funnel, but also asserts the presence of a continuous band of epiblast from which certainly the terminal vesicle of the nephridium, and doubtfully the glandular part of the tube is derived. Vezhdovsky's figures of _Rhynchelmis_ agree with those of Bergh in showing the backward growth of the nephridium from the funnel cell. There are thus substantial reasons for believing that the nephridium grows backwards from a funnel as does the coelomoduct. It is therefore by no means certain that so profound a difference embryologically can be asserted to exist between the excretory nephridia and the ducts leading from the coelom to the exterior, which are usually associated with the extrusion of the genital products among the Chaetopoda.

There are, however, anatomical and histological differences to be seen at any rate at the extremes between the undoubted nephridia of Goodrich, Meyer and Lankester, and the coelomoducts of the same authors.

[Illustration: FIG. 2. (from Goodrich).

A, Diagram of the nephridium of _Nereis diversicolor_. B, Diagram of the nephridium of _Alciope_, into which opens the large genital funnel (coelomostome). C, Small portion of the nephridium of _Glycera siphonostoma_, showing the canal cut through, and the solenocytes on the outer surface. D, Optical section of a branch of the nephridium of _Nephthys scolopendroides_. c.s, Cut surface. cst, Coelomostome. f, Flagellum. g.f, Genital funnel. n, Neck of solenocyte. n.c, Nephridial canal. n.p, Nephridiopore. nst, Nephridiostome. nu, Nucleus of solenocyte. s, Solenocytes. t, Tube.]

I. _Nephridia_.--Excretory organs which are undisputed nephridia are practically universal among the Oligochaeta, Hirudinea and Archiannelida, and occur in many Polychaeta. Their total absence has been asserted definitely only in _Paranais littoralis_. Usually these organs are present to the number of a single pair per somite, and are commonly present in the majority of the segments of the body, failing often among the Oligochaeta in a varying number of the anterior segments. They are considerably reduced in number in certain Polychaeta. Essentially, a nephridium is a tube, generally very long and much folded upon itself, composed of a string of cells placed end to end in which the continuous lumen is excavated. Such cells are termed "drain pipe" cells. Frequently the lumen is branched and may form a complicated anastomosing network in these cells. Externally, the nephridium opens by a straight part of the tube, which is often very wide, and here the intracellular lumen becomes intercellular. Rarely the nephridium does not communicate with the coelom; in such cases the nephridium ends in a single cell, like the "flame cell" of a Platyhelminth worm, in which there is a lumen blocked at the coelomic end by a tuft of fine cilia projecting into the lumen. This is so with _Aeolosoma_ (Vezhdovsky). The condition is interesting as a persistence of the conditions obtaining in the provisional nephridia of e.g. _Rhynchelmis_, which afterwards become by an enlargement and opening up of the funnel the permanent nephridia of the adult worm. In some Polychaets (e.g. _Glycera_, see fig. 2) there are many of these flame cells to a single nephridium which are specialized in form, and have been termed "solenocytes" (Goodrich). They are repeated in _Polygordius_, and are exactly to be compared with similarly-placed cells in the nephridia of _Amphioxus_.

More usually, and indeed in nearly every other case among the Oligochaeta and Hirudinea, the coelomic aperture of the nephridium consists of several cells, ciliated like the nephridium itself for a greater or less extent, forming a funnel. The funnel varies greatly in size and number of its component cells. There are so many differences of detail that no line can be drawn between the one-celled funnel of _Aeolosoma_ and the extraordinarily large and folded funnel of the posterior nephridia in the Oligochaete _Thamnodrilus_. In the last-mentioned worm the funnels of the anterior nephridia are small and but few celled; it is only the nephridia in and behind the 17th segment of the body which are particularly large and with a sinuous margin, which recall the funnels of the gonad ducts (i.e. coelomoducts).

Among the Polychaeta the nephridium of _Nereis_ (see fig. 2) is like that of the Oligochaeta and Hirudinea in that the coiled glandular tube has an intracellular duct which is ciliated in the same way in parts. The Polychaeta, however, present us with another form of nephridium seen, for example, in _Arenicola_, where a large funnel leads into a short and wide excretory tube whose lumen is intercellular. In the young stages of this worm which have been investigated by W.B. Benham, the tube, though smaller, and with a but little pronounced funnel, has still an intercellular duct. That these organs in Polychaeta serve for the removal of the generative products to the exterior is proved not only by the correspondence in number to them of the gonads, but by actual observation of the generative products in transit. This form of nephridia leads to the shorter but essentially similar organs in the Polychaete _Sternaspis_, and to those of the Echiuroidea (q.v.) and of the Gephyrea (q.v.).

Though the paired arrangement of the nephridia is the prevalent one in the Chaetopoda, there are many examples, among the Oligochaeta, of species and genera in which there are several, even many, nephridia in each segment of the body, which may or may not be connected among themselves, but have in any case separate orifices on to the exterior.

2. _Coelomoducis._--In this category are included (by Goodrich and Lankester) the gonad ducts of the Oligochaeta, certain funnels without any aperture to the exterior that have been detected in _Nereis_, &c., funnels with wide and short ducts attached to nephridia in other Polychaeta, gonad ducts in the _Capitellidae_, the gonad ducts of the leeches. In all these cases we have a duct which has a usually wide, always intercellular, lumen, generally, if not always, ciliated, which opens directly into the coelom on the one hand and on to the exterior of the body on the other. These characters are plain in all the cases cited, excepting only the leeches which will be considered separately.

There is not a great deal of difference between most of these structures and true nephridia. It is not clear, for example, to which category it is necessary to refer the excretory organs of _Arenicola_, or _Polynoe_. Both series of organs consist essentially of a ciliated tube leading from the coelom to the exterior. Both series of organs grow back centrifugally from the funnel. In both the cavity originally or immediately continuous with the coelom appears first in the funnel and grows backwards. In some cases, e.g. oviducts of Oligochaeta, sperm ducts of _Phreoryctes_, the coelomoducts occupy, like the nephridia, two segments, the funnel opening into that in front of the segment which carries the external pore. It is by no means certain that a hard and fast line can be drawn between intra- and intercellular lumina. Finally, in function there are some points of likeness. The gonad ducts of _Lumbricus_, &c., must perform one function of nephridia; they must convey to the exterior some of the coelomic fluid with its disintegrated products of waste. There is no possibility that sperm and ova can escape by these tubes not in company with coelomic fluid. In the case of many Oligochaeta where there is no vascular network surrounding the nephridium, this function must be the chief one of those glands, the more elaborate process of excretion taking place in the case of nephridia surrounded by a rich plexus of blood capillaries. A consideration of the mode of development and appearance of the coelomoducts that have thus far been enumerated (with the possible exception of those of the leeches) seems to show that there is a distinct though varying relation between them and the nephridia. It has been shown that in _Tubifex_, and some other aquatic Oligochaeta, the genital segments are at first provided with nephridia, and that these disappear on the appearance of the generative ducts, which are coelomoducts. In _Lumbricus_ the connexion is a little closer; the funnel of the nephridium, in the segments in which the funnels of the gonad ducts are to be developed, persists and is continuous with the gonad duct funnels on their first appearance. In the development of the Acanthodrilid earthworm _Octochaetus_ (F.E. Beddard) the funnels of the pronephridia disappear except in the genital segments, where they seem to be actually converted into the genital funnels. At the least there is no doubt that the genital funnels are developed precisely where the nephridial funnels formerly existed. If the genital funnels are not wholly or partly formed out of the nephridial funnels they have replaced them. In the genital segments of _Eudrilus_ the nephridia are present, but the funnels have not been found though they are obvious in other segments. Here also the genital funnels have either replaced or been formed out of nephridial funnels. In _Haplotaxis heterogyne_ (W.B. Benham) the sperm ducts are hardly to be distinguished from nephridia; they are sinuous tubes with an intra-cellular duct. But the funnel is large and thus differs from the funnels of the nephridia in adjoining segments. Here again the nephridial funnel seems to have been converted into or certainly replaced by a secondarily developed funnel. This example is similar to cases among the Polychaeta where a true nephridium is provided with a large funnel, coelomostome, according to the nomenclature of Lankester. The whole organ, having, as is thought but not known, this double origin, is termed a nephromixium. The various facts, however, seem to be susceptible of another interpretation. It may be pointed out that the several examples described recall a phenomenon which is not uncommon and is well known to anatomists. That is the replacement of an organ by, sometimes coupled with its partial conversion into, a similar or slightly different organ performing the same or an analogous function. Thus the postcaval vein of the higher vertebrata is partly a new structure altogether, and is partly formed out of the pre-existing posterior cardinals. The more complete replacements, such as the nephridia of the genital segment of _Tubifex_ by a subsequently formed genital duct, may be compared with the succession of the nesonephros to the pronephros in vertebrates, and of the metanephros to the mesonephros in the higher vertebrates. It might be well to term these structures, mostly serving as gonad ducts, which have an undoubted resemblance to nephridia, and for the most part an undoubted connexion with nephridia, "Nephrodinia," to distinguish them from another category of "ducts" which are communications between the coelom and the exterior, and which have no relation whatever to nephridia or to the organs just discussed. For these latter, the term coelomoducts might well be reserved. To this category belong certain sacs and pouches in many, perhaps most, genera of the Oligochaeta family, _Eudrilidae_, and possibly the gonad ducts in the Hirudinea. As an example of the former it has been shown (Beddard) that a large median sac in _Lybiodrilus_ is at first freely open to the coelom, that it later becomes shut off from the same, that it then acquires an external orifice, and, finally, that it encloses the ovary or ovaries, between which and the exterior a passage is thus effected. To this category will belong the oviducts in Teleostean fishes and probably the gonad ducts in several groups of invertebrates.

POLYCHAETA.--This group may be thus defined and the definition contrasted and compared with those of the other divisions of the Chaetopoda. Setae always present and often very large, much varied in form and very numerous, borne by the dorsal and ventral parapodia (when present). The prostomium and the segments generally often bear processes sensory and branchial. Eyes often present and comparatively complicated in structure. Clitellum not present as a definite organ, as in Oligochaeta. The anus is mostly terminal, and there are no anterior and posterior suckers. Nervous system often imbedded in the epidermis. Vascular system generally present forming a closed system of tubes. Alimentary canal rarely coiled, occasionally with glands which are simple caeca and sometimes serve as air reservoirs; jaws often present and an eversible pharynx. Nephridia sometimes of the type of those of the Oligochaeta; in other cases short, wide tubes with a large funnel serving also entirely or in part as gonad ducts. Frequently reduced in number of pairs; rarely (_Capitellidae_) more than one pair per segment. Gonads not so restricted in position as in Oligochaets, and often more abundant; the individuals usually unisexual. No specialized system of spermathecae, sperm reservoirs, and copulatory apparatus, as in Oligochaeta; development generally through a larval form; reproduction by budding also occurs. Marine (rarely fresh-water) in habit.

The Polychaeta contrast with the Oligochaeta by the great variety of outward form and by the frequency of specialization of different regions of the body. The head is always recognizable and much more conspicuous than in other Chaetopoda. As in the Oligochaeta the peristomial segment is often without setae, but this character is not by any means so constant as in the Oligochaeta. The prostomium bears often processes, both dorsal and ventral, which in the Sabellids are split into the circle of branchial plumes, which surround or nearly surround the mouth in those tube-dwelling Annelids. _Tomopteris_ is remarkable for the fact that the hammer-shaped prostomium has paired ventral processes each with a single seta. It is held, however, that these are a pair of parapodia which have shifted forwards. The presence of parapodia distinguish this from other groups of Chaetopoda. Typically, the parapodium consists of two processes of the body on each side, each of which bears a bundle of setae; these two divisions of the "limb" are termed respectively notopodium and neuropodium. The notopodium may be rudimentary or absent and the entire parapodium reduced to the merest ridge or even completely unrepresented. Naturally, it is among the free living forms that the parapodium is best developed, and least developed among the tubicolous Polychaeta. To each division of the parapodium belongs typically a long tentacle, the cirrus, which may be defective upon one or other of the notopodium or neuropodium, and may be developed into an arborescent gill or into a flat scale-like process, the elytron (in _Polynoe_, &c.). There are other gills developed in addition to those which represent the cirri.

_Setae_.--The setae of the Polychaeta are disposed in two bundles in many genera, but in only one bundle in such forms as have no notopodium (e.g. _Syllis_). In some genera the setae are in vertical rows, and in certain _Capitellidae_ these rows so nearly meet that an arrangement occurs reminiscent of the continuous circle of setae in the perichaetous Oligochaeta. The setae vary much in form and are often longer and stronger than in the Oligochaetes. Jointed setae and very short hooks or "uncini" (see fig. 3) are among the most remarkable forms. Simple bifid setae, such as those of Oligochaetes, are also present in certain forms.

[Illustration: Fig. 3.--a, Bristle of _Pionosyllis Malmgreni_; b, Hook of _Terebella_.]

Among the burrowing and tubicolous forms it is not uncommon for the body to be distinguishable into two or more regions; a "thorax," for example, is sharply marked off from an "abdomen" in the Sabellids. In these forms the bundles of setae are either capilliform or uncinate, and the dorsal setae of the thorax are like the ventral setae of the abdomen. It is a remarkable and newly-ascertained fact that in regeneration (in _Potamilla_) the thorax is not replaced by the growth of uninjured thoracic segments; but that the anterior segments of the abdomen take on the same characters, the setae dropping out and being replaced in accordance with the plan of the setae in the thorax of uninjured worms. Among the Oligochaeta the sexually mature worm is distinguished from the immature worm by the clitellum and by the development of genital setae. Among the Polychaeta the sexual worm is often more marked from the asexual form, so much so that these latter have been placed in different species or even genera. The alteration in form does not only affect structures used in generation; but the form of the parapodia, &c., alter. There are even dimorphic forms among the Syllids where the sexes are, as in many Polychaets, separate.

_Nephridia_.--The nephridia of the Polychaeta have been generally dealt with above in considering the nephridial system of the Chaetopoda as a whole. They contrast with those of the Oligochaeta and Hirudinea by reason of their frequently close association with the gonads, the same organ sometimes serving the two functions of excretion and conveyance of the ova and spermatozoa out of the body. On the hypothesis that such a form as _Dinophilus_ (see Haplodrili) has preserved the characters of the primitive Chaetopod more nearly than any existing Polychaet or Oligochaet, it is clear that the nephridia in the Oligochaeta have preserved the original features of those organs more nearly than most Polychaeta. Thus _Nereis_ among the latter worms, from the resemblance which its excretory system bears to that of the Oligochaeta, may be made the starting-point of a series. In this worm the paired nephridia exist in most of the segments of the body, and their form (see fig. 2) is much like that of the nephridia in the _Enchytraeidae_. The funnel, which is not large, appears to open, as a rule at least, into the segment in front of that which bears the external orifice. Quite independent of these are certain large dorsally situate funnel-like folds of the coelomic epithelium, ciliated, but of which no duct has been discovered leading to the exterior. It is possible that we have here gonad ducts distinct from nephridia which at the time of sexual maturity do open on to the exterior.

In _Polynoe_ the nephridia are short tubes with a slightly folded funnel whose lumen is intercellular, and this intercellular lumen is characteristic of the Polychaetes as contrasted with leeches and Oligochaetes. Among the Terebelloidea there is a remarkable differentiation of the nephridia into two series. One set lies in front of the diaphragm, which is the most anterior and complete septum, the rest having disappeared or being much less developed. The anterior nephridia, of which there are one to three pairs, contrast with the posterior series by their small funnels and large size, the posterior nephridia having a large funnel followed by a short tube. In _Chaetozone setosa_ the anterior nephridia occupy five segments. There is usually a gap between the two series, several segments being without nephridia. It seems that the posterior nephridia are mainly gonad ducts, and the gonads are developed in close association with the funnels. The same arrangement is found in some other Polychaetes; for instance, in _Sabellaria_ there is a single pair of large anterior nephridia, which open by a common pore, followed after an interval by large-funnelled and short nephridia. This differentiation is not, however, peculiar to the Polychaetes; for in several Oligochaetes the anterior nephridia are of large size, and opening as they do into the buccal cavity clearly play a different function to those which follow. In _Thamnodrilus_, as has been pointed out, there are two series of nephridia which resemble those of the Terebelloidea in the different sizes of their funnels. In _Lanice conchilega_ the posterior series of nephridia are connected by a thick longitudinal duct, which seems to be seen in its most reduced form in _Owenia_, where a duct on each side runs in the epidermis, being in parts a groove, and receives one short tubular nephridium only and occupies only one segment. This connexion of successive nephridia (in _Lanice_) has its counterpart in _Allolobophora, Lybiodrilus_, and apparently in the Lumbriculids _Teleuscolex_ and _Styloscolex_, among the Oligochaeta. Among the _Capitellidae_, which in several respects resemble the Oligochaeta, wide and short gonad ducts coexist in the same segments with nephridia, the latter being narrower and longer. It is noteworthy that in this family only among the Polychaeta, the nephridia are not restricted to a single pair in each segment; so that the older view that the gonad ducts are metamorphosed nephridia is not at variance with the anatomical facts which have been just stated.

_Alimentary Canal._--The alimentary canal of Polychaetes is usually a straight tube running from the anterior mouth to the posterior anus. But in some forms, e.g. _Sternaspis_, the gut is coiled. In others, again, e.g. _Cobangia_, the anus is anterior and ventral. A gizzard is present in a few forms. The buccal cavity is sometimes armed with jaws. The oesophagus is provided often with caeca which in Syllids and _Hesionidae_ have been found to contain air, and possibly therefore perform the function of the fish's air-bladder. In other Polychaetes one or more pairs of similar outgrowths are glandular. The intestine is provided with numerous branched caeca in _Aphrodite_.

[Illustration: FIG. 4.--_Dasychone infracta_, Kr. (After Malmgren.)]

_Reproduction._--As is the case with the Oligochaeta, the Polychaeta furnish examples of species which multiply asexually by budding. There is a further resemblance between the two orders of Chaetopoda in that this budding is not a general phenomenon, but confined to a few forms only. Budding, in fact, among the Polychaetes is limited to the family _Syllidae_. In the Oligochaetes it is only the families _Aeolosomatidae_ and _Naididae_ that show the same phenomenon. It has been mentioned that in the Nereids a sexual form occurs which differs structurally from the asexual worms, and was originally placed in a separate genus, _Heteronereis_; hence the name "Heteronereid" for the sexual worm. In _Syllis_ there is also a "Heterosyllid" form in which the gonads are limited to a posterior region of the body which is further marked off from the anterior non-sexual segments by the oak-like setae. In some Syllids this posterior region separates off from the rest, producing a new head; thus a process of fission occurs which has been termed schizogamy. A similar life history distinguishes certain Sabellid worms, e.g. _Filigrana_. Among the Syllids this simple state of affairs is further complicated. In _Autolytus_ there is, to begin with, a conversion of the posterior half of the body to form a sexual zooid. But before this separates off a number of other zooids are formed from a zone of budding which appears between the two first-formed individuals. Ultimately, a chain of sexual zooids is thus formed. A given stock only produces zooids of one sex. In _Myrianida_ there is a further development of this process. The conversion of the posterior end of the simple individual into a sexual region is dispensed with; but from a preanal budding segment a series of sexual buds are produced. The well-known Syllid, discovered during the voyage of the "Challenger," shows a modification of this form of budding. Here, however, the buds are lateral, though produced from a budding zone, and they themselves produce other buds, so that a ramifying colony is created.

Quite recently, another mode of budding has been described in _Trypanosyllis gemmipara_, where a crowd of some fifty buds arising symmetrically are produced at the tail end of the worm. In some Syllids, such as _Pionosyllis gestans_, the ova are attached to the body of the parent in a regular line, and develop in situ; this process, which has been attributed to budding, is an "external gestation," and occurs in a number of species.

[Illustration: FIG. 5.--A, _Autolytus_ (after Mensch) with numerous buds. B, Portion of a colony of _Syllis ramosa_ (from M'Intosh). _b.z_, Budding zone; p, anterior region of the parent worm; 1-5, buds.]

[Illustration: FIG. 6.--A, Side view of the larva of _Lopadorhynchus_ (from Kleinenberg), showing the developing trunk region. B, Side view of the trochophore larva of _Eupomatus uncinatus_ (from Hatschek).

A, Anus. E, Eye. M, Mouth. ap, Apical organ. h, "Head Kidney." i, Intestine. me, Mesoblast. ms, Larval muscle. o, Otocyst. pp, Parapodium. pr, Praeoral ciliated ring, or prototroch.]

As is very frequently the case with marine forms, as compared with their fresh-water and terrestrial allies, the Polychaeta differ from the Oligochaeta and Hirudinea in possessing a free living larval form which is hatched at an early stage in development. This larva is termed the Trochosphere larva, and typically (as it is held) is an egg-shaped larva with two bands of cilia, one preoral and one postoral, with an apical nervous plate surmounted by a tuft of longer cilia, and with a simple bent alimentary canal, with lateral mouth and posterior anus, between which and the ectoderm is a spacious cavity (blastocoel) traversed by muscular strands and often containing a larval kidney. The segmentation is of the mesoblast to begin with, and appears later behind the mouth, the part anterior to this becoming the prostomium of the adult. The chief modifications of this form are seen in the _Mitraria_ larva of _Ammochares_ with only the preoral band, which is much folded and which has provisional and long setae; the atrochous larva, where the covering of cilia is uniform and not split into bands; and the polytrochous larva where there are several bands surrounding the body. There are also other modifications.

[Illustration: FIG. 7.--_Nereis pelagica_, L. (After Oersted.)]

[Illustration: FIG. 8.--_Sabella vesiculosa_, Mont. (After Montagu.)]

[Illustration: FIG. 9. _Arenicola marina_, L.]

_Classification_.--The older arrangement of the Polychaeta into Errantia or free living and Tubicola or tube-dwelling forms will hardly fit the much increased knowledge of the group. W.B. Benham's division into Phanerocephala in which the prostomium is plain, and Crytocephala in which the prostomium is hidden by the peristomium adopted by Sedgwick, can only be justified by the character used; for the Terebellids, though phanerocephalous, have many of the features of the Sabellids. It is perhaps safer to subdivide the Order into 6 Suborders (in the number of these following Benham, except in combining the Sabelliformia and Hermelliformia). Of these 6, the two first to be considered are very plainly separable and represent the extremes of Polychaete organization, (1) _Nereidiformia_.--"Errant" Polychaetes with well-marked prostomium possessing tentacles and palps with evident and locomotor parapodia, supported (with few exceptions) by strong spines, the aciculi; muscular pharynx usually armed with jaws; septa and nephridia regularly metameric and similar throughout body; free living and predaceous. (2) _Cryptocephala_.--Tube-dwelling with body divided into thorax and abdomen marked by the setae, which are reversed in position in the neuropodium and notopodium respectively in the two regions. Parapodia hardly projecting; palps of prosomium forming branched gills; no pharynx or eversible buccal region; no septa in thorax, septa in abdomen regularly disposed. Nephridia in two series; large, anterior nephridia followed by small, short tubes in abdomen. The remaining groups are harder to define, with the exception of the (3) _Capitelliformia_, which are mud-living worms of an "oligochaetous" appearance, and with some affinities to that order. The peristomium has no setae, and the setae generally are hair-like or uncinate, often forming almost complete rings. The genital ducts are limited to one segment (the 8th in _Capitella capitata_), and there are genital setae on this and the next segment. In other forms genital ducts and nephridia coexist in the same segment. The nephridia are sometimes numerous in each segment. There is no blood system, and the coelomic corpuscles contain haemoglobin. (4) _Terebelliformia_. These worms are in some respects like the Sabellids (Cryptocephala). The parapodia, as in the Capitellidae, are hardly developed. The buccal region is unarmed and not eversible. The prostomium has many long filaments which recall the gills of the Sabellids, &c. The nephridia are specialized into two series, as in the last-mentioned worms. (5) _Spioniformia_ (including _Chaetopterus_, _Spio_, &c.) and (6) _Scoleciformia_ (_Arenicola_, _Chloraema_, _Sternaspis_) are the remaining groups. In both, the nephridia are all alike; there are no jaws; the prostomium rarely has processes. The body is often divisible into regions.

LITERATURE.--W.B. Benham, "Polychaeta" in _Cambridge Natural History_; E. Claparede, _Annelides chetopodes du golfe de Naples_ (1868 and 1870); E. Ehlers, _Die Borstenwurmer_ (1868); H. Eisig, _Die Capitelliden_ (Naples Monographs), and development of do. in _Mitth. d. zool. Stat. Neapel_ (1898); W.C. M'Intosh, _"Challenger" Reports_ (1885); E.R. Lankester, Introductory Chapter in _A Treatise on Zoology_; E.S. Goodrich, _Quart. Journ. Mic. Sci._ (1897-1900); E. Meyer, _Mitth. d. zool. Stat. Neapel_ (1887, 1888), as well as numerous other memoirs by the above and by J.T. Cunningham, de St Joseph, A. Malaquin, A. Agassiz, A.T. Watson, Malmgren, Bobretsky and A.F. Marion, E.A. Andrews, L.C. Cosmovici, R. Horst, W. Michaelsen, G. Gilson, F. Buchanan, H. Levinsen, Joyeux-Laffuie, F.W. Gamble, &c.

OLIGOCHAETA.--As contrasted with the other subdivisions of the Chaetopoda, the Oligochaeta may be thus defined. Setae very rarely absent (genus _Achaeta_) and as a rule not so large or so numerous in each segment as in the Polychaeta, and different in shape. Eyes rarely present and then rudimentary. Prostomium generally small, sometimes prolonged, but never bearing tentacles or processes. Appendages of body reduced to branchiae, present only in four species, and to the ventral copulatory appendages of _Alma_ and _Criodrilus_. Clitellum always present, extending over two (many limicolous forms) to forty-five segments (_Alma_). Segments of body numerous and not distinctive of species, being irregular and not fixed in numbers. In terrestrial forms dorsal pores are usually present; in aquatic forms a head pore only. Anus nearly always terminal, rarely dorsal, at a little distance from end of body. Suckers absent. Nervous system rarely (_Aeolosoma_) in continuity with epidermis. Vascular system always present, forming a closed system, more complicated in the larger forms than in the aquatic genera. Several specially large contractile trunks in the anterior segments uniting the dorsal and ventral vessels. Nephridia generally paired, often very numerous in each segment, in the form of long, much-coiled tubes with intracellular lumen. Gonads limited in number of pairs, testes and ovaries always present in the same individual. Special sacs developed from the intersegmental septa lodge the developing ova and sperm. Special gonad ducts always present. Male ducts often open on to exterior through a terminal chamber which is variously specialized, and sometimes with a penis.

[Illustration:

FIG. 10.--Diagrams of various Earthworms, to illustrate external characters. A, B, C, anterior segments from the ventral surface; D, hinder end of body of _Urochaeta_.

A, _Lumbricus_: 9, 10, segments containing spermathecae, the orifices of which are indicated; 14, segment bearing oviducal pores; 15, segment bearing male pores; 32, 37, first and last segments of clitellum.

B, _Acanthodrilus_: cp, orifices of spermathecae; [Female], oviducal pores; [Male], male pores; on 17th and 19th segments are the apertures of the atria.

C, _Perichaeta_: the spermathecal pores are between segments 6 and 7, 7 and 8, 8 and 9, the oviducal pores upon the 14th and the male pores upon the 18th segment.

In all the figures the nephridial pores are indicated by dots and the setae by strokes.]

Generative pores usually paired, sometimes single and median. Spermathecae nearly always present. Alimentary canal straight, often with appended glands of complicated or simpler structure; no jaws. Eggs deposited in a cocoon after copulation. Development direct. Reproduction by budding also occurs. Fresh-water (rarely marine) and terrestrial.

The Oligochaeta show a greater variety of size than any other group of the Chaetopoda. They range from a millimetre or so (smaller species of _Aeolosoma_) to 6 ft. or even rather more (_Microchaeta rappi_, &c.) in length.

_Setae._--The setae, which are always absent from the peristomial segment, are also sometimes absent from a greater number of the anterior segments of the body, and have completely disappeared in _Achaeta cameranoi._ When present they are either arranged in four bundles of from one to ten or even more setae, or are disposed in continuous lines completely encircling each segment of the body. This latter arrangement characterizes many genera of the family _Megascolicidae_ and one genus (_Periscolex_) of the _Glossoscolicidae._ It has been shown (Bourne) that the "perichaetous" condition is probably secondary, inasmuch as in worms which are, when adult, "perichaetous" the setae develop in pairs so that the embryo passes through a stage in which it has four bundles of setae, two to each bundle, the prevalent condition in the group. Rarely there is an irregular disposition of the setae which are not paired, though the total number is eight to a segment (fig. 10), e.g. _Pontoscolex._ The varying forms of the setae are illustrated in fig. 11.

[Illustration: FIG. 11.--Setae of _Oligochaeta_.

a, Penial seta of _Perichaeta ceylonica._ b, Extremity of penial seta of _Acanthodrilus_ (after Horst). c, Seta of _Urochaeta_ (Perier). d, Seta of _Lumbricus._ e, Seta of _Criodrilus._ f, g, Setae of _Bohemilla comata._ h, i, j, Setae of _Psammoryctes barbatus_ (f to j after Vezhdovsky).]

_Structure._--The body wall consists of an epidermis which secretes a delicate cuticle and is only ciliated in _Aeolosoma_, and in that genus only on the under surface of the prostomium. The epidermis contains numerous groups of sense cells; beneath the epidermis there is rarely (_Kynotus_) an extensive connective tissue dermis. Usually the epidermis is immediately followed by the circular layer of muscles, and this by the longitudinal coat. Beneath this again is a distinct peritoneum lining the coelom, which appears to be wanting as a special layer in some Polychaetes (Benham, Gilson). The muscular layers are thinner in the aquatic forms, which possess only a single row of longitudinal fibres, or (_Enchytracidae_) two layers. In the earthworms, on the other hand, this coat is thick and composed of many layers.

The clitellum consists of a thickening of the epidermis, and is of two forms among the Oligochaeta. In the aquatic genera the epidermis comes to consist entirely of glandular cells, which are, however, arranged in a single layer. In the earthworms, on the other hand, the epidermis becomes specialized into several layers of cells, all of which are glandular. It is therefore obviously much thicker than the clitellum in the limicolous forms. The position of the clitellum, which is universal in occurrence, varies much as does the number of component segments. As a rule--to which, however, there are exceptions--the clitellum consists of two or three segments only in the small aquatic Oligochaeta, while in the terrestrial forms it is as a general rule, to which again there are exceptions, a more extensive, sometimes much more extensive, region.

In the Oligochaeta there is a closer correspondence between external metamerism and the divisions of the coelom than is apparent in some Chaetopods. The external segments are usually definable by the setae; and if the setae are absent, as in the anterior segments of several _Geoscolicidae_, the nephridiopores indicate the segments; to each segment corresponds internally a chamber of the coelom which is separated from adjacent segments by transverse septa, which are only unrecognizable in the genus _Aeolosoma_ and in the head region of other Oligochaeta. In the latter case, the numerous bands of muscle attaching the pharynx to the parietes have obliterated the regular

## partition by means of septa.

_Nephridia_.--The nephridia in this group are invariably coiled tubes with an intracellular lumen and nearly invariably open into the coelom by a funnel. There are no renal organs with a wide intercellular lumen, such as occur in the Polychaeta, nor is there ever any permanent association between nephridia and ducts connected with the evacuation of the generative products, such as occur in _Alciope_, _Saccocirrus_, &c. In these points the Oligochaeta agree with the Hirudinea. They also agree in the general structure of the nephridia. It has been ascertained that the nephridia of Oligochaeta are preceded in the embryo by a pair of delicate and sinuous tubes, also found in the Hirudinea and Polychaeta, which are larval excretory organs. It is not quite certain whether these are to be regarded as the remnant of an earlier excretory system, replaced among the Oligochaeta by the subsequently developed paired structures, or whether these "head kidneys" are the first pair of nephridia precociously developed. The former view has been extensively held, and it is supported by the fact that in _Octochaetus_ the first segment of the body has a pair of nephridia which is exactly like those which follow, and, like them, persists. On the other hand, in most Oligochaeta the first segment has in the adult no nephridium, and in the case of _Octochaetus_ the existence of a "head kidney" antedating the subsequently developed nephridia of the first and other segments has neither been seen nor proved to be absent. In any case the nephridia which occupy the segments of the body generally are first of all represented by paired structures, the "pronephridia," in which the funnel is composed of but one cell, which is flagellate. This stage has at any rate been observed in _Rhynchelmis_ and _Lumbricus_ (in its widest sense) by Vezhdovsky. It is further noticeable that in _Rhynchelmis_ the covering of vesicular cells which clothes the drain-pipe cells of the adult nephridium is cut off from the nephridial cells themselves and is not a peritoneal layer surrounding the nephridium. Thus the nephridia, in this case at least, are a part of the coelom and are not shut off from it by a layer of peritoneum, as are other organs which lie in it, e.g. the gut. A growth both of the funnel, which becomes multicellular, and of the rest of the nephridium produces the adult nephridia of the genera mentioned. The paired disposition of these organs is the prevalent one among the Oligochaeta, and occurs in all of twelve out of the thirteen families into which the group is divided.

Among the _Megascolicidae_, however, which in number of genera and species nearly equals the remaining families taken together, another form of the excretory system occurs. In the genera _Pheretima, Megascolex_, _Dichogaster_, &c., each segment contains a large number of nephridia, which, on account of the fact that they are necessarily smaller than the paired nephridia of e.g. _Lumbricus_, have been termed micronephridia, as opposed to meganephridia; there is, however, no essential difference in structure, though micronephridia are not uncommonly (e.g. _Megascolides_, _Octochaetus_) unprovided with funnels. It is disputed whether these micronephridia are or are not connected together in each segment and from segment to segment. In any case they have been shown in three genera to develop by the growth and splitting into a series of original paired pronephridia. A complex network, however, does occur in _Lybiodrilus_ and certain other _Eudrilidae_, where the paired nephridia possess ducts leading to the exterior which ramify and anastomose on the thickness of the body wall. The network is, however, of the duct of the nephridium, possibly ectodermic in origin, and does not affect the glandular tubes which remain undivided and with one coelomic funnel each.

The Oligochaeta are the only Chaetopods in which undoubted nephridia may possess a relationship with the alimentary canal. Thus, in _Octochaetus multiporus_ a large nephridium opens anteriorly into the buccal cavity, and numerous nephridia in the same worm evacuate their contents into the rectum. The anteriorly-opening and usually very large nephridia are not uncommon, and have been termed "peptonephridia."

_Gonads and Gonad Ducts_.--The Oligochaeta agree with the leeches and differ from most Polychaeta in that they are hermaphrodite. There is no exception to this generalization. The gonads are, moreover, limited and fixed in numbers, and are practically invariably attached to the intersegmental septa, usually to the front septum of a segment, more rarely to the posterior septum. The prevalent number of testes is one pair in the aquatic genera and two pairs in earthworms. But there are exceptions; thus a species of _Lamprodrilus_ has four pairs of testes. The ovaries are more usually one pair, but two are sometimes present. The segments occupied by the gonads are fixed, and are for earthworms invariably X, XI, or one of them for the testes, and XIII for the ovaries The position varies in the aquatic Oligochaeta. The Oligochaeta contrast with the Polychaeta in the general presence of outgrowths of the septa in the genital segments, which are either close to, or actually involve, the gonads, and into which may also open the funnels of the gonad ducts. These sacs contain the developing sperm cells or eggs, and are with very few exceptions universal in the group. The testes are more commonly thus involved than are the ovaries. It is indeed only among the _Eudrilidae_ that the enclosure of the ovaries in septal sacs is at all general. Recently the same thing has been recorded in a few species of _Pheretima_ (= _Perichaeta_), but details are as yet wanting. We can thus speak in these worms of _gonocoels_, i.e. coelomic cavities connected only with the generative system. These cavities communicate with the exterior through the gonad ducts, which have nothing to do with them, but whose coelomic funnels are taken up by them in the course of their growth. There are, however, in the _Eudrilidae_, as already mentioned, sacs envolving the ovaries which bore their own way to the exterior, and thus may be termed coelomoducts. These sacs are dealt with later under the description of the spermathecae, which function they appear to perform. The gonad ducts are male and female, and open opposite to or, rarely, alongside of the gonads, whose products they convey to the exterior. The oviducts are always short trumpet-shaped tubes and are sometimes reduced (_Enchytraeidae_) to merely the external orifices. It is possible, however, that those oviducts belong to a separate morphological category, more comparable to the dorsal pores and to abdominal pores in some fishes. The sperm ducts are usually longer than the oviducts; but in Limicolae both series of tubes opening by the funnel into one segment and on to the exterior in the following segment. While the oviducts always open directly on to the exterior, it is the rule for the sperm ducts to open on to the exterior near to or through certain terminal chambers, which have been variously termed atrium and prostate, or spermiducal gland. The distal extremity of this apparatus is sometimes eversible as a penis. Associated with these glands are frequently to be found bundles or pairs of long and variously modified setae which are termed penial setae, to distinguish them from other setae sometimes but not always associated with rather similar glands which are found anteriorly to these, and often in the immediate neighbourhood of the spermathecae; the latter are spoken of as genital setae.

[Illustration: FIG. 12.--Female reproductive system of _Heliodrilus_.--XI-XIV, eleventh to fourteenth segments, sperm, spermatheca; sp.o, its external orifice; sp.sac, spermathecal sac; ov, sac containing ovary; r.o, egg sac; od, oviduct.]

_Spermathecae._--These structures appear to be absolutely distinctive of the Oligochaeta, unless the sacs which contain sperm and open in common with the nephridia of _Saccocirrus_ (see HAPLODRILI) are similar. Spermathecae are generally present in the Oligochaeta and are absent only in comparatively few genera and species. Their position varies, but is constant for the species, and they are rarely found behind the gonads. They are essentially spherical, pear-shaped or oval sacs opening on to the exterior but closed at the coelomic end. In a few _Enchytraeidae_ and _Lumbriculidae_ the spermathecae open at the distal extremity into the oesophagus, which is a fact difficult of explanation. Among the aquatic Oligochaeta and many earthworms (the families _Lunibricidae_, _Geoscolicidae_ and a few other genera) the spermathecae are simple structures, as has been described. In the majority of the _Megascolicidae_ each sac is provided with one or more diverticula, tubular or oval in form, of a slightly different histological character in the lining epithelium, and in them is invariably lodged the sperm.

The spermathecae are usually paired structures, one pair to each of the segments where they occur. In many _Geoscolicidae_, however, and certain _Lumbricidae_ and _Perichaetidae_, there are several, even a large number, of pairs of very small spermathecae to each of the segments which contain them.

In the _Eudrilidae_ there are spermathecae of different morphological value. In figs. 12 and 13 are shown the spermathecae of the genera _Hyperiodrilus_ and _Heliodrilus_, which are simple sacs ending blindly as in other earthworms, but of which there is only one median opening in the thirteenth segment or in the eleventh. In _Heliodrilus_ the blind extremity of the spermatheca is enclosed in a coelomic sac which is in connexion with the sacs envolving the ovaries and oviducts. In _Hyperiodrilus_ the whole spermatheca is thus included in a corresponding sac, which is of great extent. In such other genera of the family as have been examined, the true spermatheca has entirely disappeared, and the sac which contains it in _Hyperiodrilus_ alone remains. This sac has been already referred to as a coelomoduct. Its orifice on to the exterior is formed by an involution (as it appears) of the epidermis, and that it performs the function of a spermatheca is shown by its containing spermatozoa, or, in _Stuhlmannia_, a spermatophore. In _Polytoreutus_, also, spermatophores have been found in these spermathecal sacs. We have thus the replacement of a spermatheca, corresponding to those of the remaining families of Oligochaeta, and derived, as is believed, from the epidermis, by a structure performing the same function, but derived from the mesoblastic tissues, and with a cavity which is coelom.

_Alimentary Canal._--The alimentary canal is always a straight tube, and the anus, save in the genera _Criodrilus_ and _Dero_, is completely terminal. A buccal cavity, a pharynx, an oesophagus and an intestine are always distinguishable. Commonly among the terrestrial forms there is a gizzard, or two gizzards, or a larger number, in the oesophageal region. There is no armed protrusible pharynx, such as exists in some other Chaetopods. This may be associated with mud-eating habits; but it is not wholly certain that this is the case; for in _Chaetogaster_ and _Agriodrilus_, which are predaceous worms, there is no protrusible pharynx, though in the latter the oesophagus is thickened through its extent with muscular fibres. The oesophagus is often furnished with glandular diverticula, the "glands of Morren," which are often of complex structure through the folding of their walls. Among the purely aquatic families such structures are very rare, and are represented by two caeca in the genus _Limnodriloides_. It is a remarkable fact, not yet understood, that in certain _Enchytraeidae_ and _Lumbriculidae_ the spermathecae open into the oesophagus as well as on to the exterior. The only comparable fact among other worms is the Laurer's canal or genito-intestinal canal in the Trematoda. The intestine is usually in the higher forms provided with a typhlosole, in which, in _Pontoscolex_, runs a ciliated canal or canals communicating with the intestine. It is possible that this represents the syphon or supplementary intestine of _Capitellidae_, which has been shown to develop as a grooving of the intestine ultimately cut off from it. The intestine has a pair of caeca or two or three pairs (but all lie in one segment) in the genus _Pheretima_ and in one species of _Rhinodrilus_. In _Typhoeus_ and _Megascolex_ there are complex glands appended to the intestine.

[Illustration: FIG. 13.--Female reproductive system of _Hyperiodrilus_.--XIII, XIV, thirteenth and fourteenth segments.

sp, Spermatheca. sp', Spermathecal sac involving the last. ov, Ovary. r.o, Egg sac. od, Oviduct.]

In _Benhamia caecifera_ and at least one other earthworm there are numerous caeca, one pair to each segment.

_Classification._--The classifications of Adolf Eduard, Grube and Claparede separated into two subdivisions the aquatic and the terrestrial forms. This scheme, opposed by many, has been reinstated by Sedgwick. The chief difficulty in this scheme is offered by the Moniligastridae, which in some degree combine the characters of both the suborders, into neither of which will they fit accurately. The following arrangement is a compromise:--

Group I. _Aphaneura._--This group is referred by A. Sedgwick to the Archiannelida. It is, however, though doubtless near to the base of the Oligochaetous series, most nearly allied in the reproductive system to the Oligochaeta. It contains but one family, _Aeolosomatidae_. There are three pairs of spermathecae situated in segments III-V, a testis in V and an ovary in VI. There are a clitellum and sperm ducts which though like nephridia have a larger funnel and a less complexly wound duct. This family consists of only one well-known genus, _Aeolosoma_, which contains several species. They are minute worms with coloured oil drops (green, olive green or orange) contained in the epidermis. The nervous system is embedded in the epidermis, and the pairs of ganglia are separated as in _Serpula_, &c.; each pair has a longish commissure between its two ganglia. The intersegmental septa are absent save for the division of the first segment. The large prostomium is ciliated ventrally. The setae are either entirely capillary or there are in addition some sigmoid setae even with bifid free extremities. This genus also propagates asexually, like _Ctenodrilus_, which may possibly belong to the same family. Asexual reproduction universal.

Group II. _Limicolae._--With a few exceptions the Limicolae are, as the name denotes, aquatic in habit. They are small to moderate-sized Oligochaeta, with a smaller number of segments than in the Terricolae. The alimentary canal is simple and a gizzard or oesophageal diverticula rarely developed. The vascular system is simple with as a rule direct communication between dorsal and ventral vessels in each segment. Nerve cord lies in coelom; brain in first segment or prostomium in many forms. Clitellum generally only two or three segments and more anterior in position than in Terricolae. Nephridia always paired and without plexus of blood capillaries. Spermatheca rarely with diverticula; sperm ducts as a rule occupying two segments only, usually opening by means of an atrium. Sperm sacs generally occupying a good many segments and with simple interior undivided by a network of trabeculae. Ova large and with much yolk. Asexual reproduction only in Naids. Egg sacs as large or nearly so as sperm sacs. Testes and ovaries always free. The following families constitute the group, viz. _Naididae_, _Enchytraeidae_, _Tubificidae_, _Lumbriculidae_, _Phreoryctidae_, _Phreodrilidae_, _Alluroididae_, the latter possibly not referable to this group.

Group III. _Moniligastres._--Moderate-sized to very large Oligochaeta, terrestrial in habit, with the appearance of Terricolae. Generative organs anterior in position as in Limicolae. Sperm ducts and atria as in Limicolae; egg sacs large; body wall thick; vascular system and nephridia as in Terricolae. Only one family, _Moniligastridae_.

Group IV. _Terricolae._--Earthworms, rarely aquatic in habit. Of small to very large size. Clitellum commonly extensive and more posterior in position than in other groups. Vascular system complicated without regular connexion between dorsal and ventral vessels, except in anterior segments. Nephridia as a rule with abundant vascular supply. Testes, and occasionally ovaries, enclosed in sacs. Sperm sacs generally limited to one or two segments with interior subdivided by trabeculae. Sperm ducts traverse several segments on their way to exterior. They open in common with, or near to, or, more rarely, into, glands which are not certainly comparable to the atria of the Limicolae. Egg sacs minute and functionless(?). Eggs minute with little yolk. Nephridia sometimes very numerous in each segment. Spermathecae often with diverticula.

Earthworms are divided into the following families, viz. _Megascolicidae_, _Geoscolicidae_, _Eudrilidae_, _Lumbricidae_.

As an appendix to the Oligochaeta, and possibly referable to that group, though their systematic position cannot at present be determined with certainty, are to be placed the _Bdellodrilidae_ (_Discodrilidae_ auct.), which are small parasites upon crayfish. These worms lay cocoons like the Oligochaeta and leeches, and where they depart from the structure of the Oligochaeta agree with that of leeches. The body is composed of a small and limited number of segments (not more than fourteen), and there is a sucker at each end of the body. There are no setae and apparently only two pairs of nephridia, of which the anterior pair open commonly by a common pore on the third segment after the head, whose segments have not been accurately enumerated. The intervening segments contain the genitalia, which are on the Oligochaeta plan in that the gonads are independent of their ducts and that there are special spermathecae, one pair. The male ducts are either one pair or two pairs, which open by a common and complicated efferent terminal apparatus furnished with a protrusible penis. The ganglia are crowded at the posterior end of the body as in leeches, and there is much tendency to the obliteration of the coelom as in that group. _Pterodrilus_ and _Cirrodrilus_ bear a few, or circles of, external processes which may be branchiae; _Bdellodrilus_ and _Astacobdella_ have none. The vascular system is as in the lower Oligochaeta. There are two chitinous jaws in the buccal cavity, a dorsal and a ventral, which are of specially complicated structure in _Cirrodrilus_.

LITERATURE.--F.E. Beddard, _A Monograph of the Oligochaeta_ (Oxford, 1895), also _Quart. Journ. Micr. Sci._, 1886-1895, and _Proc. Zool. Soc._, 1885-1906; W.B. Benham, _Quart. Journ. Micr. Sci._, 1886-1905; W. Michaelsen, "Oligochaeta" in _Das Tierreich_, 1900, and _Mitth. Mus._ (Hamburg, 1890-1906); A.G. Bourne, _Quart. Journ. Micr. Sci._, 1894; H.J. Moore, _Journ. Morph._, 1895; F. Vezhdovsky, _System d. Oligochaeten_ (Prague, 1884), and _Entwicklungsgeschichtliche Untersuchungen_; and numerous papers by the above and by G. Eisen, E. Perrier, D. Rosa, R. Horst, L. Cognetti, U. Pierantoni, W. Baldwin Spencer, H. Ude, &c., and embryological memoirs by R.S. Bergh, E.B. Wilson, N. Kleinenberg, &c.

HIRUDINEA.--The leeches are more particularly to be compared with the Oligochaeta, and the following definition embraces the main features in which they agree and disagree with that group. Setae are only present in the genus _Acanthobdella_. Eyes are present, but hardly so complex as in certain genera of Polychaetes. The appendages of the body are reduced to branchiae, present in certain forms. A clitellum is present. The segments of body are few (not more than thirty-four) and fixed in number. The anus is dorsal. One or two (anterior and posterior) suckers always present. Nervous system always in coelom. Coelom generally reduced to a system of tubes, sometimes communicating with vascular system; in _Acanthobdella_ and _Ozobranchus_ a series of metamerically arranged chambers as in Oligochaeta. Nephridia always paired, rarely (_Pontobdella_) forming a network communicating from segment to segment; lumen of nephridia always intracellular, funnels pervious or impervious. Alimentary canal sometimes with protrusible proboscis; never with gizzard or oesophageal glands; intestine with caeca as a rule. Jaws often present. Testes several pairs, rarely one pair, continuous with sperm ducts; ovaries, one pair, continuous with oviducts; generative pores single and median. No separate spermathecae or septal chambers for the development of the ova and sperm. Eggs deposited in a cocoon. Development direct. No asexual generation. Fresh-water, marine and terrestrial. Parasitic or carnivorous.

In external characters the Hirudinea are unmistakable and not to be confused with other Annelids, except perhaps with the _Bdellodrilidae_, which resemble them in certain particulars. The absence of setae--save in _Acanthobdella_, where five of the anterior segments possess each four pairs of setae with reserve setae placed close behind them (fig. 14), and the presence of an anterior and posterior sucker, produce a looping mode of progression similar to that of a Geometrid larva. The absence of setae and the great secondary annulation render the mapping of the segments a subject of some difficulty. The most reliable test appears to be the nerve ganglia, which are more distinct from the intervening connectives than in other Annelids.

[Illustration: FIG. 14.--_Acanthobdella_, from the ventral surface, showing the five sets of setae (S1 to S5) and the replacing setae (Sr) behind them. The three pairs of pigmented spots show the position of the eyes on the dorsal surface. (After Kovalevsky.)]

In the middle of the body, where the limits of the somites can be checked by a comparison with the arrangement of the nephridia and the gonads, and where the ganglia are quite distinct and separated by long connectives, each ganglion is seen to consist of six masses of cells enclosed by capsules and to give off three nerves on each side. This corresponds to the usual presence (in the _Rhynchobdellidae_) of three annuli to each segment. Anteriorly and posteriorly separate ganglia have fused. The brain consists not only of a group of six capsules corresponding to the archicerebrum of the Oligochaeta, but of a further mass of cells surrounding and existing below the alimentary canal, which can be analysed into five or six more separate ganglia. The whole mass lies in the seventh or eighth segment. At the posterior end of the body there are likewise seven separate ganglia partially fused to form a single ganglionic mass, which innervates the segments lying behind the anus and corresponding to the posterior sucker. So that a leech in which only twenty-seven segments are apparent by the enumeration of the annuli, separate ganglia, nephridia, lines of sensillae upon the body, really possesses an additional seven lying behind that which is apparently the last of the series and crowded together into a minute space. The annuli into which segments are externally divided are so deeply incised as to render it impossible to distinguish, as can be readily done in the Oligochaeta as a rule, the limits of an annulus from that of a true segment. As remarked, the prevalent number of annuli to a segment is three in the _Rhynchobdellidae_. But in that group (_Cystobranchus_) there may be as many as eight annuli. In the _Gnathobdellidae_ the prevailing number of annuli to a segment is five; but here again the number is often increased, and _Trocheta_ has no less than eleven. The reason for this excessive annulation has been seen in the limited number of segments (thirty-four) of which the body is composed, which are laid down early and do not increase. In the Oligochaeta, on the other hand, there is growth of new segments. It is important to notice that the metameric plan of growth of Chaetopods is still preserved.

The nephridia are like those of the Oligochaeta in general structure; that is to say, they consist of drain-pipe cells which are placed end to end and are perforated by their duct. The internal funnel varies in the same way as in the Oligochaeta in the number of cells which form it. In _Clepsine_ (_Glossiphonia_) there are only three cells, and in _Nephelis_ five to eight cells. In _Hirudo_ the funnel is not pervious and is composed of a large number of cells. Externally, the nephridium opens by a vesicle, as in many Oligochaetes whose lumen is intercellular. In _Pontobdella_ and _Branchellion_ the nephridia form a network extending from segment to segment, but there is only one pair of funnels in each segment. Slight differences in form have been noted between nephridia of different segments; but the Hirudinea do not show the marked differentiation that is to be seen in some other Chaetopods; nor do the nephridia ever acquire any relations to the alimentary canal.

[Illustration: FIG. 15.--Section of _Acanthobdella_ (after Kovalevsky).

c, Coelom. c.ch, Coelomic epithelium (yellow-cells). cg, Glandular cells. cl, Muscle cells of lateral line. cp, Pigment cells. ep, Ectoderm. g, Nerve cord. m, Intestine. mc, Circular muscle. ml, Longitudinal muscle. vd, Dorsal vessel. vv, Ventral vessel.]

[Illustration: FIG. 16.--Section of _Acanthobdella_ (after Kovalevsky). Identical letters as in fig. 2; in addition, cn, nerve cord; in, intestine; nf, parts of nephridium; on, external opening of nephridium; ov, ova; t, testis.]

_Coelom._--The coelom of the Hirudinea differs in most genera from that of the Oligochaeta and Polychaeta. The difference is that it is broken up into a complex sinus system. The least modified type is shown by _Acanthobdella_, a leech, parasitic upon fishes, in which transverse sections (see figs. 15 and 16) show the gut, the nervous system, &c., lying in a spacious chamber which is the coelom. This coelom is lined by peritoneal cells and is divided into a series of metameres by septa which correspond to the segmentation of the body, the arrangement being thus precisely like that of typical Chaetopoda. Moreover, upon the intestine the coelomic cells are modified into chloragogen cells. In _Acanthobdella_ the testes are, however, not contained in the general coelom, and the nephridia lie in the septa. It is remarkable, in view of the spaciousness of the coelom, that the funnels of the latter have not been seen. _Ozobranchus_ possesses a coelom which is less typically chaetopodous than that of _Acanthobdella_, but more so than in other leeches. There is a spacious cavity surrounding the gut and containing also blood-vessels, and to some extent the generative organs, and the nervous cord. Furthermore, in the mid region of the body this coelom is broken up by metamerically arranged septa, as in _Acanthobdella_. These septa are, however, rather incomplete and are not fastened to the gut; and, as in _Acanthobdella_, the nephridia are embedded in them. In addition to the median lacuna there are two lateral lacunae, one upon each side. These regions of the coelom end at the ends of the body and communicate with each other by means of a branched system of coelomic sinuses, which are in places very fine tubes. Neither in this genus nor in the last is there any communication between coelom and vascular system. In _Clepsine_ (_Glossiphonia_) there is a further breaking up of the coelom. The median lacuna no longer exists, but is represented by a dorsal and ventral sinus. The former lodges the dorsal, the latter the ventral, blood-vessel. The gut has no coelomic space surrounding it. A complex network places these sinuses and the lateral sinuses in communication. Here also the blood system has no communication with the sinus system of the coelom. In _Hirudo_ and the _Gnathobdellidae_ there is only one system of cavities which consist of four principal longitudinal trunks, of which the two lateral are contractile, which communicate with a network ramifying everywhere, even among the cells of the epidermis. The network is partly formed out of pigmented cells which are excavated and join to form tubes, the so-called botryoidal tissue, not found among the _Rhynchobdellidae_ at all. It seems clear from the recent investigations of A.G. Bourne and E.S. Goodrich that the vascular system and the coelom are in communication (as in vertebrates by means of the lymph system). On the other hand, it has been held that in these leeches there is no vascular system at all and that the entire system of spaces is coelom. In favour of regarding the vascular system as totally absent, is the fact that the median coelomic channels contain no dorsal and ventral vessel. In favour of seeing in the lateral trunks and their branches a vascular system, is the contractility of the former, and the fact of the intrusion of the latter into the epidermis, matched among the Oligochaeta, where undoubted blood capillaries perforate the epidermis. A further fact must be considered in deciding this question, which is the discovery of ramifying coelomic tubes, approaching close to, but not entering, the epidermis in the Polychaete _Arenicola_. These tubes are lined by flattened epithelium and often contain blood capillaries; they communicate with the coelom and are to be regarded as prolongation of it into the thickness of the body wall.

_Gonads and Gonad Ducts._--The gonads and their ducts in the Hirudinea invariably form a closed system of cavities entirely shut off from the coelom in which they lie. There is thus a broad resemblance to the _Eudrilidae_, to which group of Oligochaeta the Hirudinea are further akin by reason of the invariably unpaired condition of the generative apertures, and the existence of a copulatory apparatus (both of which characters, however, are present occasionally in other Oligochaeta).

The testes are more numerous than the ovaries, of which latter there are never more than one pair. The testes vary in numbers of pairs. Four (_Ozobranchus_) to six (_Glossiphonia_) or ten (_Philaemon_) are common numbers. In _Acanthobdella_, however, the testes of each side of the body have grown together to form a continuous band, which extends in front of external pore. Each testis communicates by means of an efferent duct with a common collecting duct of its side of the body, which opens on to the exterior by means of a protrusible penis, and to which is sometimes appended a seminal vesicle. The efferent ducts are ciliated, and there is a patch of cilia at the point where they communicate with the cavity of each testis. The ovaries are more extensive in some forms (e.g. _Ozobranchus_) than in others, where they are small rounded bodies. The two ducts continuous with the gonads open by a common vagina on to the exterior behind the male pores. This "vagina" is sometimes of exaggerated size. Thus, in _Philaemon pungens_ (Lambert) it has the form of a large sac, into which open by a single orifice the conjoined oviducts. From this vagina arises a narrow duct leading to the exterior. In _Ozobranchus_ the structures in question are still more complicated. The two long ovarian sacs communicate with each other by a transverse bridge before uniting to form the terminal canal. Into each ovarian sac behind the transverse junction opens a slender tube, which is greatly coiled, and, in its turn, opens into a spherical "spermathecal sac." From this an equally slender tube proceeds, which joins its fellow of the opposite side, and the two form a thick, walled tube, which opens on to the exterior within the bursa copulatrix through which the penis protrudes. These two last-mentioned types show features which can be, as it seems, matched in the Eudrilidae.

The gonads develop (O. Burger) in coelomic spaces close to nephridial funnels, which have, however, no relation to the gonad ducts. The ovaries are solid bodies, of which the outer layer becomes separated from the plug of cells lying within; thus a cavity is formed which is clearly coelom. This cavity and its walls becomes prolonged to form the oviducts. A stage exactly comparable to the stage in the leeches, where the ovary is surrounded by a closed sac, has been observed in _Eudrilus_. In this Annelid later the sac in question joins its fellow, passing beneath the nerve cord exactly as in the leech, and also grows out to reach the exterior. The sole difference is therefore that in _Eudrilus_ the ovarian sac gives rise to a tube which bifurcates, one branch meeting a corresponding branch of the other ovary of the pair, while the second branch reaches the exterior. In the leech the two branches are fused into one. We have here clearly a case of a true coelomoduct performing the function of an oviduct in both leeches and _Eudrilidae_. The facts just referred to suggest further comparisons between the Hirudinea and _Eudrilidae_. The large sacs which have been termed vagina are suggestive of the large coelomic spermathecae in Eudrilids, a comparison which needs, however, embryological data, not at present forthcoming, for its justification. It is at least clear that in _Ozobranchus_ this comparison is justifiable; but only probable, or perhaps possible, in the case of _Philaemon_. In the former, the duct, leading from the ovarian sac, and swelling along its course into the spherical sac, the "spermatheca," is highly suggestive of the oviduct and receptaculum of the _Eudrilidae_.

The testes during development become hollowed out and are prolonged into the vasa efferentia. These ducts therefore have not their exact counterparts in the Oligochaeta, unless we are to assume that they collectively are represented by the seminal vesicles of earthworms and the vasa deferentia. It is to be noted that the Hirudinea differ from the Oligochaeta in that the male pore is in advance of the gonads (except in _Acanthobdella_, which here, as in so many points, approximates to the Oligochaeta), whereas in Oligochaeta that pore is behind the gonads (again with an exception, _Allurus_).

_Classification_.--The Hirudinea may be divided into three families:--

(i.) _Rhynchobdellidae_.--A protrusible proboscis exists, but there are no jaws. The blood is colourless. _Pontobdella_, _Glossiphonia_, &c.

(ii.) _Gnathobdellidae_.--A proboscis absent, but jaws usually present. Blood coloured red with haemoglobin. _Hirudo_, _Nephelis_, &c.

(iii.) _Acanthobdellidae_.--Proboscis present, but short. Paired setae of Oligochaetous pattern present in anterior segments. Blood red. _Acanthobdella_.

LITERATURE.--A.O. Kovalevsky, _Bull. Imp. Sci._ (St Petersburg, November 1896) (_Acanthobdella_); A.G. Bourne, _Quart. Journ. Micr. Sci._, 1884; A. Oka, _Zeitschr. wiss. Zool._, 1894; E.S. Goodrich, _Quart. Journ. Micr. Sci._, 1899; W.E. Castle, _Bull. Mus. Comp. Zool._, 1900; A.M. Lambert, _Proc. Roy. Soc._ (Victoria, 1897); C.O. Whitman, _Journ. Morph._, 1889 and 1891; O. Burger, _Zeitschr. wiss. Zool._, 1902, and other memoirs by the above, and by St V. Apathy, R. Blanchard, H. Bolsius, A. Dendy, R.S. Bergh, &c. (F. E. B.)

CHAETOSOMATIDA, a small group of minute, free-living, aquatic organisms which are usually placed as an annex to the Nematoda. Indeed Mechnikov, to whom we owe much of our knowledge of these forms, calls them "creeping Nematoda." They are usually found amongst seaweed in temperate seas, but they are probably widely distributed; some are fresh-water. The genus _Chaetosoma_, with the two species _Ch. claparedii_ and _Ch. ophicephalum_ and the genus _Tristicochaeta_, have swollen heads. The third genus _Rhabdogaster_ has no such distinct head, though the body may be swollen anteriorly. The mouth is terminal and anterior and surrounded by a ring of spicules or a half-ring of hooks. Scattered hairs cover the body. Just in front of the anus there is in _Chaetosoma_ a double, and in _Tristicochaeta_ a triple row of about fifteen stout cylindrical projections upon which the animals creep. The females are a little larger than the males; in _Ch. claparedii_ the former attain a length of 1.5 mm., the latter of 1.12 mm. The mouth opens into an oesophagus which passes into an intestine; this opens by a ventral anus situated a little in front of the posterior end. The testis is single, and its duct opens with the anus, and is provided with a couple of spicules. The ovary is double, and the oviducts open by a median ventral pore about the middle of the body; in this region there is a second swelling both in _Chaetosoma_ and in _Rhabdogaster_. The last-named form is in the female 0.36 mm. in length. In it the hairs are confined to the dorsal middle line and the creeping setae are hooked, of a finer structure than in _Chaetosoma_, and situated so far forward that the vagina opens amongst them. _Ch. ophicephalum_ has been taken in the English Channel.

[Illustration: From _Cambridge Natural History_, vol. ii. "Worms." by permission of Macmillan & Co., Ltd.

Mature female of _Chaetosoma daparedii_, (From Mechnikov.) a, Oesophagus; b, intestine; c, anus; d, ovary; e, generative pore; f, ventral bristles.]

See E. Mechnikov, _Zeitschr. wiss. Zool._ xvii., 1867, p. 537; Panceri, _Atti Acc. Napoli_, vii., 1878, p. 7. (A. E. S.)

CHAFER, a word used in modern speech to distinguish the beetles of the family _Scarabaeidae_, and more especially those species which feed on leaves in the adult state. The word is derived from the O. Eng. _ceafor_, and it is interesting to note that the cognate Ger. _Kafer_ is applied to beetles of all kinds. For the characters of the _Scarabaeidae_ see COLEOPTERA. This family includes a large number of beetles, some of which feed on dung and others on vegetable tissues. The cockchafers and their near allies belong to the subfamily _Melolonthinae_, and the rose-chafers to the _Cetoniinae_; in both the beetles eat leaves, and their grubs spend a long life underground devouring roots. In Britain the Melolonthines that are usually noted as injurious are the two species of cockchafer (_Melolontha vulgaris_ and _M. hippocastani_), large heavy beetles with black pubescent pro-thorax, brown elytra and an elongated pointed tail-process; the summer-chafer (_Rhizotrogus solstitialis_), a smaller pale brown chafer; and the still smaller garden-chafer or "cocker-bundy" (_Phyllopertha horticola_), which has a dark green pro-thorax and brown elytra. Of the Cetoniines, the beautiful metallic green rose-chafer, _Cetonia aurata_, sometimes causes damage, especially in gardens. The larvae of the chafers are heavy, soft-skinned grubs, with hard brown heads provided with powerful mandibles, three pairs of well-developed legs, and a swollen abdomen. As they grow, the larvae become strongly flexed towards the ventral surface, and lie curled up in their earthen cells, feeding on roots. The larval life lasts several years, and in hard frosts the grubs go deep down away from the surface. Pupation takes place in the autumn, and though the perfect insect emerges from the cuticle very soon afterwards, it remains in its underground cell for several months, not making its way to the upper air until the ensuing summer. After pairing, the female crawls down into the soil to lay her eggs. The grubs of chafers, when turned up by the plough, are greedily devoured by poultry, pigs and various wild birds. When the beetles become so numerous as to call for destruction, they are usually shaken off the trees where they rest on to sheets or tarred boards. On the continent of Europe chafers are far more numerous than in the United Kingdom, and the rural governments in France give rewards for their destruction. D. Sharp states that in the department of Seine-inferieure 867,173,000 cockchafers and 647,000,000 larvae were killed in the four years preceding 1870.

The anatomy of _Melolontha_ is very fully described in a classical memoir by H.E. Strauss-Durckheim (Paris, 1828). (G. H. C.)

CHAFF (from the A.S. _ceaf_, allied to the O. High Ger. _cheva_, a husk or pod), the husks left after threshing grain, and also hay and straw chopped fine as food for cattle; hence, figuratively, the refuse or worthless part of anything. The colloquial use of the word, to chaff, in the sense of to banter or to make fun of a person, may be derived from this figurative sense, or from "to chafe," meaning to vex or irritate.

CHAFFARINAS, or ZAITARINES, a group of islands belonging to Spain off the north coast of Morocco, near the Algerian frontier, 2-1/2 m. to the north of Cape del Agna. The largest of these isles, Del Congreso, is rocky and hilly. It has a watch-house on the coast nearest to Morocco. Isabella II., the central island, contains several batteries, barracks and a penal convict settlement. The Spanish government has undertaken the construction of breakwaters to unite this island with the neighbouring islet of El Rey, with a view to enclose a deep and already sheltered anchorage. This roadstead affords a safe refuge for many large vessels. The Chaffarinas, which are the _Tres Insulae_ of the Romans and the _Zafran_ of the Arabs, were occupied by Spain in 1848. The Spanish occupation anticipated by a few days a French expedition sent from Oran to annex the islands to Algeria. The population of the islands is under 1000.

CHAFFEE, ADNA ROMANZA (1842- ), American general, was born at Orwell, Ohio, on the 14th of April 1842. At the outbreak of the Civil War he entered the United States cavalry as a private, and he rose to commissioned rank in 1863, becoming brevet captain in 1865. He remained in the army after the war and took part with distinction in many Indian campaigns. His promotion was, however, slow, and he was at the age of fifty-six still a lieutenant-colonel of cavalry. But in 1898, at the outbreak of the Spanish-American War, he was made brigadier-general and soon afterwards major-general of volunteers. In the Cuban campaign he won

## particular distinction, and the victory of the Americans in the action of

El Caney was in large measure due to his careful personal reconnaissances of the ground to be attacked and to the endurance of his own brigade. After reverting for a time to the rank of brigadier-general, he was made a major-general U.S.V. again in 1900 and was appointed to command the United States contingent in China. He took a brilliant and successful

## part in the advance on Peking and the relief of the Legations. In 1901 he

became a major-general in the regular army, and in 1901-1902 commanded the Division of the Philippines. In 1902-1903 he commanded the Department of the East, and from 1904 to 1906 was chief of the general staff of the army. In 1904 he received the rank of lieutenant-general in the United States army, being the first enlisted man of the regular army to attain this, the highest rank in the service. He was retired at his own request on the 1st of February 1906, after more than forty years' service.

CHAFFINCH (_Fringilla coelebs_), the common English name of a bird belonging to the family _Fringillidae_ (see FINCH), and distinguished, in the male sex, by the deep greyish blue of its crown feathers, the yellowish green of its rump, the white of the wing coverts, so disposed as to form two conspicuous bars, and the reddish brown passing into vinous red of the throat and breast. The female is drab, but shows the same white markings as the male, and the young males resemble the females until after the first autumn moult, when they gradually assume the plumage of their sex. The chaffinch breeds early in the season, and its song may often be heard in February. Its nest, which is a model of neatness and symmetry, it builds on trees and bushes, preferring such as are overgrown with moss and lichens. It is chiefly composed of moss and wool, lined internally with grass, wool, feathers, and whatever soft material the locality affords. The outside consists of moss and lichens, and according to Selby, "is always accordant with the particular colour of its situation." When built in the neighbourhood of towns the nest is somewhat slovenly and untidy, being often composed of bits of dirty straw, pieces of paper and blackened moss; in one instance, near Glasgow, the author of the _Birds of the West of Scotland_ found several postage-stamps thus employed. It lays four or five eggs of a pale purplish buff, streaked and spotted with purplish red. In spring the chaffinch is destructive to early flowers, and to young radishes and turnips just as they appear above the surface; in summer, however, it feeds principally on insects and their larvae, while in autumn and winter its food consists of grain and other seeds. On the continent of Europe the chaffinch is a favourite song-bird, especially in Germany, where great attention is paid to its training.

CHAFING-DISH (from the O. Fr. _chaufer_, to make warm), a kind of portable grate heated with charcoal, and used for cooking or keeping food warm. In a light form, and heated over a spirit lamp, it is also used for cooking various dainty dishes at table. The employment of the chafing-dish for the latter purpose has been largely restored in modern cookery.

CHAGOS, a group of atolls in the Indian Ocean, belonging to Britain, disposed in circular form round the Chagos bank, in 4 deg. 44' to 7 deg. 39' S., and 70 deg. 55' to 72 deg. 52' E. The atolls on the south and east side of the bank, which has a circumference of about 270 m., have disappeared through subsidence; a few--Egmont, Danger, Eagle, and Three Brothers--still remain on the east side, but most of the population (about 700) is centred on Diego Garcia, which lies on the south-east side, and is nearly 13 m. long by 6 m. wide. The lagoon, which is enclosed by two coral barriers and accessible to the largest vessels on the north side, forms one of the finest natural harbours in the world. The group, which has a total land area of 76 sq. m., is dependent for administrative purposes on Mauritius, and is regularly visited by vessels from that colony. The only product is cocoa-nut oil, of which about 106,000 gallons are annually exported. The French occupied the islands in 1791 from Mauritius, and the oil industry (from which the group is sometimes called the Oil Islands) came into the hands of French Creoles.

CHAGRES, a village of the Republic of Panama, on the Atlantic coast of the Isthmus, at the mouth of the Chagres river, and about 8 m. W. of Colon. It has a harbour from 10 to 12 ft. deep, which is difficult to enter, however, on account of bars at its mouth. The port was discovered by Columbus in 1502, and was opened for traffic with Panama, on the Pacific coast, by way of the Chagres river, in the 16th century. With the decline of Porto Bello in the 18th century Chagres became the chief Atlantic port of the Isthmus, and was at the height of its importance during the great rush of gold-hunters across the Isthmus to California in 1849 and the years immediately following. With the completion of the Panama railway in 1855, however, travel was diverted to Colon, and Chagres soon became a village of miserable huts, with no evidence of its former importance. On a high rock at the mouth of the river stands the castle of Lorenzo, which was destroyed by Sir Henry Morgan when he captured the town in 1671, but was rebuilt soon afterwards by the Spaniards. Chagres was again captured in 1740 by British forces under Admiral Edward Vernon.

CHAIN (through the O. Fr. _choeine_, _choene_, &c., from Lat. _catena_), a series of links of metal or other material so connected together that the whole forms a flexible band or cord. Chains are used for a variety of purposes, such as fastening, securing, or connecting together two or more objects, supporting or lifting weights, transmitting mechanical power, &c.; or as an ornament to serve as a collar, as a symbol of office or state, or as part of the insignia of an order of knighthood; or as a device from which to hang a jewelled or other pendant, a watch, &c. (see COLLAR). Ornamental chains are made with a great variety of links, but those intended for utilitarian purposes are mostly of two types. In stud chains a stud or brace is inserted across each link to prevent its sides from collapsing inwards under strain, whereas in open link chains the links have no studs. The addition of studs is reckoned to increase the load which the chain can safely bear by 50%. Small chains of the open-link type are to a great extent made by machinery. For larger sizes the smith cuts off a length of iron rod of suitable diameter, forms it while hot to the shape of the link by repeated blows of his hammer, and welds together the two ends of the link, previously slipped inside its fellow, by the aid of the same tool; in some cases the bending is done in a mechanical press and the welding under a power hammer (see also CABLE). Weldless chains are also made; in A.G. Strathern's process, for instance, cruciform steel bars are pressed, while hot, into links, each without join and engaging with its neighbours. Chains used for transmitting power are known as pitch-chains; the chain of a bicycle (q.v.) is an example.

From the use of the chain as employed to bind or fetter a prisoner or slave, comes the figurative application to anything which serves as a constraining or restraining force; and from its series of connected links, to any series of objects, events, arguments, &c., connected by succession, logical sequence or reasoning. Specific uses are for a measuring line in land-surveying, consisting of 100 links, i.e. iron rods, 7.92 in. in length, making 22 yds. in all, hence a lineal measure of that length; and, as a nautical term, for the contrivance by which the lower shrouds of a mast are extended and secured to the ship's sides, consisting of dead-eyes, chain-plates, and chain-wale or "channel."

CHAIR (in. Mid. Eng. _choere_, through O. Fr. _chaere_ or _chaiere_, from Lat. _cathedra_, later _caledra_, Gr. [Greek: kathedra], seat, cf. "cathedral"; the modern Fr. form _chaise_, a chair, has been adopted in English with a particular meaning as a form of carriage; _chaire_ in French is still used of a professorial or ecclesiastical "chair," or _cathedra_), a movable seat, usually with four legs, for a single person, the most varied and familiar article of domestic furniture. The chair is of extreme antiquity, although for many centuries and indeed for thousands of years it was an appanage of state and dignity rather than an article of ordinary use. "The chair" is still extensively used as the emblem of authority in the House of Commons and in public meetings. It was not, in fact, until the 16th century that it became common anywhere. The chest, the bench and the stool were until then the ordinary seats of everyday life, and the number of chairs which have survived from an earlier date is exceedingly limited; most of such examples are of ecclesiastical or seigneurial origin. Our knowledge of the chairs of remote antiquity is derived almost entirely from monuments, sculpture and paintings. A few actual examples exist in the British Museum, in the Egyptian museum at Cairo, and elsewhere. In ancient Egypt they appear to have been of great richness and splendour. Fashioned of ebony and ivory, or of carved and gilded wood, they were covered with costly stuffs and supported upon representations of the legs of beasts of the chase or the figures of captives. An arm-chair in fine preservation found in a tomb in the Valley of the Kings is astonishingly similar, even in small details, to that "Empire" style which followed Napoleon's campaign in Egypt. The earliest monuments of Nineveh represent a chair without a back but with tastefully carved legs ending in lions' claws or bulls' hoofs; others are supported by figures in the nature of caryatides or by animals. The earliest known form of Greek chair, going back to five or six centuries before Christ, had a back but stood straight up, front and back. On the frieze of the Parthenon Zeus occupies a square seat with a bar-back and thick turned legs; it is ornamented with winged sphinxes and the feet of beasts. The characteristic Roman chairs were of marble, also adorned with sphinxes; the curule chair was originally very similar in form to the modern folding chair, but eventually received a good deal of ornament.

The most famous of the very few chairs which have come down from a remote antiquity is the reputed chair of St Peter in St Peter's at Rome. The wooden portions are much decayed, but it would appear to be Byzantine work of the 6th century, and to be really an ancient _sedia gestatoria_. It has ivory carvings representing the labours of Hercules. A few pieces of an earlier oaken chair have been let in; the existing one, Gregorovius says, is of acacia wood. The legend that this was the curule chair of the senator Pudens is necessarily apocryphal. It is not, as is popularly supposed, enclosed in Bernini's bronze chair, but is kept under triple lock and exhibited only once in a century. Byzantium, like Greece and Rome, affected the curule form of chair, and in addition to lions' heads and winged figures of Victory and dolphin-shaped arms used also the lyre-back which has been made familiar by the pseudo-classical revival of the end of the 18th century. The chair of Maximian in the cathedral of Ravenna is believed to date from the middle of the 6th century. It is of marble, round, with a high back, and is carved in high relief with figures of saints and scenes from the Gospels--the Annunciation, the Adoration of the Magi, the flight into Egypt and the baptism of Christ. The smaller spaces are filled with carvings of animals, birds, flowers and foliated ornament. Another very ancient seat is the so-called "Chair of Dagobert" in the Louvre. It is of cast bronze, sharpened with the chisel and partially gilt; it is of the curule or faldstool type and supported upon legs terminating in the heads and feet of animals. The seat, which was probably of leather, has disappeared. Its attribution depends entirely upon the statement of Suger, abbot of St Denis in the 12th century, who added a back and arms. Its age has been much discussed, but Viollet-le-Duc dated it to early Merovingian times, and it may in any case be taken as the oldest faldstool in existence. To the same generic type belongs the famous abbots' chair of Glastonbury; such chairs might readily be taken to pieces when their owners travelled. The _faldisterium_ in time acquired arms and a back, while retaining its folding shape. The most famous, as well as the most ancient, English chair is that made at the end of the 13th century for Edward I., in which most subsequent monarchs have been crowned. It is of an architectural type and of oak, and was covered with gilded _gesso_ which long since disappeared.

Passing from these historic examples we find the chair monopolized by the ruler, lay or ecclesiastical, to a comparatively late date. As the seat of authority it stood at the head of the lord's table, on his dais, by the side of his bed. The seigneurial chair, commoner in France and the Netherlands than in England, is a very interesting type, approximating in many respects to the episcopal or abbatial throne or stall. It early acquired a very high back and sometimes had a canopy. Arms were invariable, and the lower part was closed in with panelled or carved front and sides--the seat, indeed, was often hinged and sometimes closed with a key. That we are still said to sit "in" an arm-chair and "on" other kinds of chairs is a reminiscence of the time when the lord or seigneur sat "in his chair." These throne-like seats were always architectural in character, and as Gothic feeling waned took the distinctive characteristics of Renaissance work. It was owing in great measure to the Renaissance that the chair ceased to be an appanage of state, and became the customary companion of whomsoever could afford to buy it. Once the idea of privilege faded the chair speedily came into general use, and almost at once began to reflect the fashions of the hour. No piece of furniture has ever been so close an index to sumptuary changes. It has varied in size, shape and sturdiness with the fashion not only of women's dress but of men's also. Thus the chair which was not, even with its arms purposely suppressed, too ample during the several reigns of some form or other of hoops and farthingale, became monstrous when these protuberances disappeared. Again, the costly laced coats of the dandy of the 18th and early 19th centuries were so threatened by the ordinary form of seat that a "conversation chair" was devised, which enabled the buck and the ruffler to sit with his face to the back, his valuable tails hanging unimpeded over the front. The early chair almost invariably had arms, and it was not until towards the close of the 16th century that the smaller form grew common.

The majority of the chairs of all countries until the middle of the 17th century were of oak without upholstery, and when it became customary to cushion them, leather was sometimes employed; subsequently velvet and silk were extensively used, and at a later period cheaper and often more durable materials. Leather was not infrequently used even for the costly and elaborate chairs of the faldstool form--occasionally sheathed in thin plates of silver--which Venice sent all over Europe. To this day, indeed, leather is one of the most frequently employed materials for chair covering. The outstanding characteristic of most chairs until the middle of the 17th century was massiveness and solidity. Being usually made of oak, they were of considerable weight, and it was not until the introduction of the handsome Louis XIII. chairs with cane backs and seats that either weight or solidity was reduced. Although English furniture derives so extensively from foreign and especially French and Italian models, the earlier forms of English chairs owed but little to exotic influences. This was especially the case down to the end of the Tudor period, after which France began to set her mark upon the British chair. The squat variety, with heavy and sombre back, carved like a piece of panelling, gave place to a taller, more slender, and more elegant form, in which the framework only was carved, and attempts were made at ornament in new directions. The stretcher especially offered opportunities which were not lost upon the cabinet-makers of the Restoration. From a mere uncompromising cross-bar intended to strengthen the construction it blossomed, almost suddenly, into an elaborate scroll-work or an exceedingly graceful semicircular ornament connecting all four legs, with a vase-shaped knob in the centre. The arms and legs of chairs of this period were scrolled, the splats of the back often showing a rich arrangement of spirals and scrolls. This most decorative of all types appears to have been popularized in England by the cavaliers who had been in exile with Charles II. and had become familiar with it in the north-western parts of the European continent. During he reign of William and Mary these charming forms degenerated into something much stiffer and more rectangular, with a solid, more or less fiddle-shaped splat and a cabriole leg with pad feet. The more ornamental examples had cane seats and ill-proportioned cane backs. From these forms was gradually developed the Chippendale chair, with its elaborately interlaced back, its graceful arms and square or cabriole legs, the latter terminating in the claw and ball or the pad foot. Hepplewhite, Sheraton and Adam all aimed at lightening the chair, which, even in the master hands of Chippendale, remained comparatively heavy. The endeavour succeeded, and the modern chair is everywhere comparatively slight. Chippendale and Hepplewhite between them determined what appears to be the final form of the chair, for since their time practically no new type has lasted, and in its main characteristics the chair of the 20th century is the direct derivative of that of the later 18th.

The 18th century was, indeed, the golden age of the chair, especially in France and England, between which there was considerable give and take of ideas. Even Diderot could not refrain from writing of them in his _Encyclopedie_. The typical Louis Seize chair, oval-backed and ample of seat, with descending arms and round-reeded legs, covered in Beauvais or some such gay tapestry woven with Boucher or Watteau-like scenes, is a very gracious object, in which the period reached its high-water mark. The Empire brought in squat and squabby shapes, comfortable enough no doubt, but entirely destitute of inspiration. English Empire chairs were often heavier and more sombre than those of French design. Thenceforward the chair in all countries ceased to attract the artist. The _art nouveau_ school has occasionally produced something of not unpleasing simplicity; but more often its efforts have been frankly ugly or even grotesque. There have been practically no novelties, with the exception perhaps of the basket-chair and such like, which have been made possible by modern command over material. So much, indeed, is the present indebted to the past in this matter that even the revolving chair, now so familiar in offices, has a pedigree of something like four centuries (see also SEDAN-CHAIR). (J. P.-B.)

CHAISE (the French for "chair," through a transference from a "sedan-chair" to a wheeled vehicle), a light two- or four-wheeled carriage with a movable hood or "calash"; the "post-chaise" was the fast-travelling carriage of the 18th and early 19th centuries. It was closed and four-wheeled for two or four horses and with the driver riding postillion.

CHAKRATA, a mountain cantonment in the Dehra Dun district of the United Provinces of India, on the range of hills overlooking the valleys of the Jumna and the Tons, at an elevation of 7000 ft. It was founded in 1866 and first occupied in April 1869.

CHALCEDON, more correctly CALCHEDON (mod. _Kadikeui_), an ancient maritime town of Bithynia, in Asia Minor, almost directly opposite Byzantium, south of Scutari. It was a Megarian colony founded on a site so obviously inferior to that which was within view on the opposite shore, that it received from the oracle the name of "the City of the Blind." In its early history it shared the fortunes of Byzantium, was taken by the satrap Otanes, vacillated long between the Lacedaemonian and the Athenian interests, and was at last bequeathed to the Romans by Attalus III. of Pergamum (133 B.C.). It was partly destroyed by Mithradates, but recovered during the Empire, and in A.D. 451 was the seat of the Fourth General Council. It fell under the repeated attacks of the barbarian hordes who crossed over after having ravaged Byzantium, and furnished an encampment to the Persians under Chosroes, c. 616-626. The Turks used it as a quarry for building materials for Constantinople. The site is now occupied by the village of Kadikeui ("Village of the Judge"), which forms the tenth "cercle" of the municipality of Constantinople. Pop. about 33,000, of whom 8000 are Moslems. There is a large British colony with a church, and also Greek and Armenian churches and schools, and a training college for Roman Catholic Armenians. To the S. are the ruins of Panteichion (mod. _Pendik_), where Belisarius is said to have lived in retirement.

See J. von Hammer, _Constantinopolis_ (Pesth, 1822); Murray's _Handbook for Constantinople_ (London, 1900).

CHALCEDON, COUNCIL OF, the fourth ecumenical council of the Catholic Church, was held in 451, its occasion being the Eutychian heresy and the notorious "Robber Synod" (see EUTYCHES and EPHESUS, COUNCIL OF), which called forth vigorous protests both in the East and in the West, and a loud demand for a new general council, a demand that was ignored by the Eutychian Theodosius II., but speedily granted by his successor, Marcian, a "Flavianist." In response to the imperial summons, five to six hundred bishops, all Eastern, except the Roman legates and two Africans, assembled in Chalcedon on the 8th of October 451. The bishop of Rome claimed for his legates the right to preside, and insisted that any act that failed to receive their approval would be invalid. The first session was tumultuous; party feeling ran high, and scurrilous and vulgar epithets were bandied to and fro. The acts of the Robber Synod were examined; fraud, violence and coercion were charged against it; its entire proceedings were annulled, and, at the third session, its leader, Dioscurus, was deposed and degraded. The emperor requested a declaration of the true faith; but the sentiment of the council was opposed to a new symbol. It contented itself with reaffirming the Nicene and Constantinopolitan creeds and the Ephesine formula of 431, and accepting, only after examination, the Christological statement contained in the _Epistola Dogmatica_ of Leo I. (q.v.) to Flavianus. Thus the council rejected both Nestorianism and Eutychianism, and stood upon the doctrine that Christ had two natures, each perfect in itself and each distinct from the other, yet perfectly united in one person, who was at once both God and man. With this statement, which was formally subscribed in the presence of the emperor, the development of the Christological doctrine was completed, but not in a manner to obviate further controversy (see MONOPHYSITES and MONOTHELITES).

The remaining sessions, vii.-xvi., were occupied with matters of discipline, complaints, claims, controversies and the like. Canons were adopted, thirty according to the generally received tradition, although the most ancient texts contain but twenty-eight, and, as Hefele points out, the so-called twenty-ninth and thirtieth are properly not canons, but repetitions of proposals made in a previous session.

The most important enactments of the council of Chalcedon were the following: (1) the approval of the canons of the first three ecumenical councils and of the synods of Ancyra, Neo-Caesarea, Changra, Antioch and Laodicea; (2) forbidding trade, secular pursuits and war to the clergy, bishops not even being allowed to administer the property of their dioceses; (3) forbidding monks and nuns to marry or to return to the world; likewise forbidding the establishment of a monastery in any diocese without the consent of the bishop, or the disestablishment of a monastery once consecrated; (4) punishing with deposition an ordination or clerical appointment made for money; forbidding "absolute ordination" (i.e. without assignment to a particular charge), the translation of clerics except for good cause, the enrolment of a cleric in two churches at once, and the performance of sacerdotal functions outside of one's diocese without letters of commendation from one's bishop; (5) confirming the jurisdiction of bishops over all clerics, regular and secular alike, and punishing with deposition any conspiracy against episcopal authority; (6) establishing a gradation of ecclesiastical tribunals, viz. bishop, provincial synod, exarch of the diocese, patriarch of Constantinople (obviously the council could not here have been legislating for the entire church); forbidding clerics to be running to Constantinople with complaints, without the consent of their respective bishops; (7) confirming the possession of rural parishes to those who had actually administered them for thirty years, providing for the adjudication of conflicting claims, and guaranteeing the integrity of metropolitan provinces; (8) confirming the third canon of the second ecumenical council, which accorded to Constantinople equal privileges ([Greek: isa presbeia]) with Rome, and the second rank among the patriarchates, and, in addition, granting to Constantinople patriarchal jurisdiction over Pontus, Asia and Thrace.

The Roman legates, who were absent (designedly?) when this famous twenty-eighth canon was adopted, protested against it, but in vain, the imperial commissioners deciding in favour of its regularity and validity. Leo I., although he recognized the council as ecumenical and confirmed its doctrinal decrees, rejected canon xxviii. on the ground that it contravened the sixth canon of Nicaea and infringed the rights of Alexandria and Antioch. In what proportion zeal for the ancient canons and the rights of others, and jealous fear of encroachment upon his own jurisdiction, were mixed in the motives of Leo, it would be interesting to know. The canon was universally received in the East, and was expressly confirmed by the Quinisext Council, 692 (see CONSTANTINOPLE, COUNCILS OF).

The emperor Marcian approved the doctrinal decrees of the council and enjoined silence in regard to theological questions. Eutyches and Dioscurus and their followers were deposed and banished. But harmony was not thus to be restored; hardly had the council dissolved when the church was plunged into the Monophysite controversy.

See Mansi vi. pp. 529-1102, vii. pp. 1-868; Hardouin ii. pp. 1-772; Hefele (2nd ed.) ii. pp. 394-578 (English translation, iii. pp. 268-464); also extended bibliographies in Herzog-Hauck, _Realencyklopadie_, 3rd ed., s.v. "Eutyches" (by Loofs) and s.v. "Nestorianer" (by Kessler). (T. F. C.)

CHALCEDONY, or CALCEDONY (sometimes called by old writers cassidoine), a variety of native silica, often used as an ornamental stone. The present application of the term is comparatively modern. The "chalcedonius" of Pliny was quite a different mineral, being a green stone from the copper-mines of Chalcedon, in Asia Minor, whence the name. There has been some confusion between chalcedony and the ancient "carcedonia," a stone which seems to have been a carbuncle from Africa, brought by way of Carthage ([Greek: Karchedon]). Our chalcedony was probably included by the ancients among the various kinds of jasper and agate, especially the varieties termed "leucachates" and "cerachates."

By modern mineralogists the name chalcedony is restricted to those kinds of silica which occur not in distinct crystals like ordinary quartz, but in concretionary, mammillated or stalactitic forms, which break with a fine splintery fracture, and display a delicate fibrous structure. Chalcedony may be regarded as a micro-crystalline form of quartz. It is rather softer and less dense than crystallized quartz, its hardness being about 6.5 and its specific gravity 2.6, the difference being probably due to the presence of a small amount of opaline silica between the fibres. Chalcedony is a translucent substance of rather waxy lustre, presenting great variety of colours, though usually white, grey, yellow or brown. A rare blue chalcedony is sometimes polished under the name of "sapphirine"--a term applied also to a distinct mineral (an aluminium-magnesium silicate) from Greenland.

Chalcedony occurs as a secondary mineral in volcanic rocks, representing usually the silica set free by the decomposition of various silicates, and deposited in cracks, forming veins, or in vesicular hollows, forming amygdales. Its occurrence gives the name to Chalcedony Park, Arizona. It is found in the basalts of N. Ireland, the Faroe Isles and Iceland: it is common in the traps of the Deccan in India, and in volcanic rocks in Uruguay and Brazil. Certain flat oval nodules from a decomposed lava (augite-andesite) in Uruguay present a cavity lined with quartz crystals and enclosing liquid (a weak saline solution), with a movable air-bubble, whence they are called "enhydros" or water-stones. Very fine examples of stalactitic chalcedony, in whimsical forms, have been yielded by some of the Cornish copper-mines. The surface of chalcedony is occasionally coated with a delicate bluish bloom. A chalcedonic deposit in the form of concentric rings, on fossils and fragments of limestone in S. Devon, is known as "orbicular silica" or "beekite," having been named after Dr Henry Beeke, dean of Bristol, who first directed attention to such deposits. Certain pseudomorphs of chalcedony after datolite, from Haytor in Devonshire, have received the name of "haytorite." Optical examination of many chalcedonic minerals by French mineralogists has shown that they are aggregates of various fibrous crystalline bodies differing from each other in certain optical characters, whence they are distinguished as separate minerals under such names as calcedonite, pseudocalcedonite, quartzine, lutecite and lussatite. Many coloured and variegated chalcedonies are cut and polished as ornamental stones, and are described under special headings. Chalcedony has been in all ages the commonest of the stones used by the gem-engraver.

See AGATE, BLOODSTONE, CARNELIAN, CHRYSOPRASE, HELIOTROPE, MOCHA STONE, ONYX, SARD and SARDONYX. (F. W. R.*)

CHALCIDICUM, in Roman architecture, the vestibule or portico of a public building opening on to the forum; as in the basilica of Eumactria at Pompeii, and the basilica of Constantine at Rome, where it was placed at one end.

CHALCIS, the chief town of the island of Euboea in Greece, situated on the strait of the Euripus at its narrowest point. The name is preserved from antiquity and is derived from the Greek [Greek: chalkos] (copper, bronze), though there is no trace of any mines in the neighbourhood. Chalcis was peopled by an Ionic stock which early developed great industrial and colonizing activity. In the 8th and 7th centuries it founded thirty town-ships on the peninsula of Chalcidice, and several important cities in Sicily (q.v.). Its mineral produce, metal-work, purple and pottery not only found markets among these settlements, but were distributed over the Mediterranean in the ships of Corinth and Samos. With the help of these allies Chalcis engaged the rival league of its neighbour Eretria (q.v.) in the so-called Lelantine War, by which it acquired the best agricultural district of Euboea and became the chief city of the island. Early in the 6th century its prosperity was broken by a disastrous war with the Athenians, who expelled the ruling aristocracy and settled a cleruchy on the site. Chalcis subsequently became a member of both the Delian Leagues. In the Hellenistic period it gained importance as a fortress by which the Macedonian rulers controlled central Greece. It was used by kings Antiochus III. of Syria (192) and Mithradates VI. of Pontus (88) as a base for invading Greece. Under Roman rule Chalcis retained a measure of commercial prosperity; since the 6th century A.D. it again served as a fortress for the protection of central Greece against northern invaders. From 1209 it stood under Venetian control; in 1470 it passed to the Ottomans, who made it the seat of a pasha. In 1688 it was successfully held against a strong Venetian attack. The modern town has about 10,000 inhabitants, and maintains a considerable export trade which received an impetus from the establishment of railway connexion with Athens and Peiraeus (1904). It is composed of two parts--the old walled town towards the Euripus, called the Castro, where the Jewish and Turkish families who have remained there mostly dwell; and the more modern suburb that lies outside it, which is chiefly occupied by the Greeks. A part of the walls of the Castro and many of the houses within it were shaken down by the earthquake of 1894; part has been demolished in the widening of the Euripus. The most interesting object is the church of St Paraskeve, which was once the chief church of the Venetians; it dates from the Byzantine period, though many of its architectural features are Western. There is also a Turkish mosque, which is now used as a guard-house.

AUTHORITIES.--Strabo vii. fr. 11, x. p. 447; Herodotus v. 77; Thucydides i. 15; _Corpus Inscr. Atticarum_, iv. (1) 27a, iv. (2) 10, iv. (2) p. 22; W.M. Leake, _Travels in Northern Greece_ (London, 1835), ii. 254-270; E. Curtius in _Hermes_, x. (1876), p. 220 sqq.; A. Holm, _Lange Fehde_ (Berlin, 1884); H. Dondorff, _De Rebus Chalcidensium_ (Gottingen, 1869); for coinage, B.V. Head, _Historia Numorum_ (Oxford, 1887), pp. 303-5; and art. NUMISMATICS: _Greek_ S Euboea.

CHALCONDYLES[1] (or CHALCOCONDYLAS), LAONICUS, the only Athenian Byzantine writer. Hardly anything is known of his life. He wrote a history, in ten books, of the period from 1298-1463, describing the fall of the Greek empire and the rise of the Ottoman Turks, which forms the centre of the narrative, down to the conquest of the Venetians and Mathias, king of Hungary, by Mahommed II. The capture of Constantinople he rightly regarded as an historical event of far-reaching importance, although the comparison of it to the fall of Troy is hardly appropriate. The work incidentally gives a quaint and interesting sketch of the manners and civilization of England, France and Germany, whose assistance the Greeks sought to obtain against the Turks. Like that of other Byzantine writers, Chalcondyles' chronology is defective, and his adherence to the old Greek geographical nomenclature is a source of confusion. For his account of earlier events he was able to obtain information from his father, who was one of the most prominent men in Athens during the struggles between the Greek and Frankish nobles. His model is Thucydides (according to Bekker, Herodotus); his language is tolerably pure and correct, his style simple and clear. The text, however, is in a very corrupt state.

_Editio princeps_, ed. J.B. Baumbach (1615); in Bonn _Corpus Scriptorum Hist. Byz._ ed. I. Bekker (1843); Migne, _Patrologia Graeca_, clix. There is a French translation by Blaise de Vigenere (1577, later ed. by Artus Thomas with valuable illustrations on Turkish matters); see also F. Gregorovius, _Geschichte der Stadt Athen im Mittelalter_, ii. (1889); Gibbon, _Decline and Fall_, ch. 66; C. Krumbacher, _Geschichte der byzantinischen Litteratur_ (1897). There is a biographical sketch of Laonicus and his brother in Greek by Antonius Calosynas, a physician of Toledo, who lived in the latter part of the 16th century (see C. Hopf, _Chroniques greco-romanes_, 1873).

His brother, DEMETRIUS CHALCONDYLES (1424-1511), was born in Athens. In 1447 he migrated to Italy, where Cardinal Bessarion gave him his patronage. He became famous as a teacher of Greek letters and the Platonic philosophy; in 1463 he was made professor at Padua, and in 1479 he was summoned by Lorenzo de' Medici to Florence to fill the professorship vacated by John Argyropoulos. In 1492 he removed to Milan, where he died in 1511. He was associated with Marsilius Ficinus, Angelus Politianus, and Theodorus Gaza, in the revival of letters in the western world. One of his pupils at Florence was the famous John Reuchlin. Demetrius Chalcondyles published the editio princeps of Homer, Isocrates, and Suidas, and a Greek grammar (_Erotemata_) in the form of question and answer.

See H. Hody, _De Graecis illustribus_ (1742); C. Hopf, _Chroniques greco-romanes_ (1873); E. Legrand, _Bibliographic hellenique_, i. (1885).

FOOTNOTE:

[1] A shortened form of Chalcocondyles, from [Greek: chalkos], copper, and [Greek: kondylos], knuckle.

CHALDAEA. The expressions "Chaldaea" and "Chaldaeans" are frequently used in the Old Testament as equivalents for "Babylonia" and "Babylonians." Chaldaea was really the name of a country, used in two senses. It was first applied to the extreme southern district, whose ancient capital was the city of _Bit Yakin_, the chief seat of the renowned Chaldaean rebel Merodach-baladan, who harassed the Assyrian kings Sargon and Sennacherib. It is not as yet possible to fix the exact boundaries of the original home of the Chaldaeans, but it may be regarded as having been the long stretch of alluvial land situated at the then separate mouths of the Tigris and Euphrates, which rivers now combine to flow into the Persian Gulf in the waters of the majestic _Shatt el 'Arab_.

The name "Chaldaea," however, soon came to have a more extensive application. In the days of the Assyrian king Ramman-nirari III. (812-783 B.C.), the term _mat Kaldu_ covered practically all Babylonia. Furthermore, Merodach-baladan was called by Sargon II. (722-705 B.C.) "king of the land of the Chaldaeans" and "king of the land of Bit Yakin" after the old capital city, but there is no satisfactory evidence that Merodach-baladan had the right to the title "Babylonian." The racial distinction between the Chaldaeans and the Babylonians proper seems to have existed until a much later date, although it is almost certain that the former were originally a Semitic people. That they differed from the Arabs and Aramaeans is also seen from the distinction made by Sennacherib (705-681 B.C.) between the Chaldaeans and these races. Later, during the period covering the fall of Assyria and the rise of the Neo-Babylonian empire, the term _mat Kaldu_ was not only applied to all Babylonia, but also embraced the territory of certain foreign nations who were later included by Ezekiel (xxiii. 23) under the expression "Chaldaeans."

As already indicated, the Chaldaeans were most probably a Semitic people. It is likely that they first came from Arabia, the supposed original home of the Semitic races, at a very early date along the coast of the Persian Gulf and settled in the neighbourhood of Ur ("Ur of the Chaldees," Gen. xi. 28), whence they began a series of encroachments,

## partly by warfare and partly by immigration, against the other Semitic

Babylonians. These aggressions after many centuries ended in the Chaldaean supremacy of Nabopolassar and his successors (c. 626 ff.), although there is no positive proof that Nabopolassar was purely Chaldaean in blood. The sudden rise of the later Babylonian empire under Nebuchadrezzar, the son of Nabopolassar, must have tended to produce so thorough an amalgamation of the Chaldaeans and Babylonians, who had theretofore been considered as two kindred branches of the same original Semite stock, that in the course of time no perceptible differences existed between them. A similar amalgamation, although in this case of two peoples originally racially distinct, has taken place in modern times between the Manchu Tatars and the Chinese. It is quite evident, for example, from the Semitic character of the Chaldaean king-names, that the language of these Chaldaeans differed in no way from the ordinary Semitic Babylonian idiom which was practically identical with that of Assyria. Consequently, the term "Chaldaean" came quite naturally to be used in later days as synonymous with "Babylonian." When subsequently the Babylonian language went out of use and Aramaic took its place, the latter tongue was wrongly termed "Chaldee" by Jerome, because it was the only language known to him used in Babylonia. This error was followed until a very recent date by many scholars.

The derivation of the name "Chaldaean" is extremely uncertain. Peter Jensen has conjectured with slight probability that the Chaldaeans were Semitized Sumerians, i.e. a non-Semitic tribe which by contact with Semitic influences had lost its original character. There seems to be little or no evidence to support such a view. Friedrich Delitzsch derived the name "Chaldaean" =_Kasdim_ from the non-Semitic Kassites who held the supremacy over practically all Babylonia during an extended period (c. 1783-1200 B.C.). This theory seems also to be extremely improbable. It is much more likely that the name "Chaldaean" is connected with the Semitic stem _kasadu_ (conquer), in which case _Kaldi-Kasdi_, with the well-known interchange of l and _s_, would mean "conquerors." It is also possible that _Kasdu-Kaldu_ is connected with the proper name Chesed, who is represented as having been the nephew of Abraham (Gen. xxii. 22). There is no connexion whatever between the Black Sea peoples called "Chaldaeans" by Xenophon (_Anab_. vii. 25) and the Chaldaeans of Babylonia.

In Daniel, the term "Chaldaeans" is very commonly employed with the meaning "astrologers, astronomers," which sense also appears in the classical authors, notably in Herodotus, Strabo and Diodorus. In Daniel i. 4, by the expression "tongue of the Chaldaeans," the writer evidently meant the language in which the celebrated Babylonian works on astrology and divination were composed. It is now known that the literary idiom of the Babylonian wise men was the non-Semitic Sumerian; but it is not probable that the late author of Daniel (c. 168 B.C.) was aware of this fact.

The word "Chaldaean" is used in Daniel in two senses. It is applied as elsewhere in the Old Testament as a race-name to the Babylonians (Dan. iii. 8, v. 30, ix. 1); but the expression is used oftener, either as a name for some special class of magicians, or as a term for magicians in general (ix. 1). The transfer of the name of the people to a special class is perhaps to be explained in the following manner. As just shown, "Chaldaean" and "Babylonian" had become in later times practically synonymous, but the term "Chaldaean" had lived on in the secondary restricted sense of "wise men." The early _Kaldi_ had seized and held from very ancient times the region of old Sumer, which was the centre of the primitive non-Semitic culture. It seems extremely probable that these Chaldaean Semites were so strongly influenced by the foreign civilization as to adopt it eventually as their own. Then, as the Chaldaeans soon became the dominant people, the priestly caste of that region developed into a Chaldaean institution. It is reasonable to conjecture that southern Babylonia, the home of the old culture, supplied Babylon and other important cities with priests, who from their descent were correctly called "Chaldaeans." This name in later times, owing to the racial amalgamation of the Chaldaeans and Babylonians, lost its former national force, and became, as it occurs in Daniel, a distinctive appellation of the Babylonian priestly class. It is possible, though not certain, that the occurrence of the word _kalu_ (priest) in Babylonian, which has no etymological connexion with _Kaldu_, may have contributed paronomastically towards the popular use of the term "Chaldaeans" for the Babylonian Magi. (See also ASTROLOGY.)

LITERATURE.--Delattre, _Les Chaldeens jusqu'a la fond. de l'emp. de Nebuch._ (1889); Winckler, _Untersuchungen zur altor. Gesch._ (1889), pp. 49 ff.; _Gesch. Bab. u. Assyr._ (1892), pp. 111 ff.; Prince, _Commentary on Daniel_ (1899), pp. 59-61; see also BABYLONIA AND ASSYRIA and SUMER AND SUMERIAN. (J. D. Pr.)

CHALDEE, a term sometimes applied to the Aramaic portions of the biblical books of Ezra and Daniel or to the vernacular paraphrases of the Old Testament (see TARGUM). The explanation formerly adopted and embodied in the name Chaldee is that the change took place in Babylon. That the so-called Biblical Chaldee, in which considerable portions of the books of Ezra and Daniel are written, was really the language of Babylon was supposed to be clear from Dan. ii. 4, where the Chaldaeans are said to have spoken to the king in Aramaic. But the cuneiform inscriptions show that the language of the Chaldaeans was Assyrian; and an examination of the very large part of the Hebrew Old Testament written later than the exile proves conclusively that the substitution of Aramaic for Hebrew as the vernacular of Palestine took place very gradually. Hence scholars are now agreed that the term "Chaldee" is a misnomer, and that the dialect so called is really the language of the South-Western Arameans, who were the immediate neighbours of the Jews (W. Wright, _Comparative Grammar of the Semitic Languages_, p. 16). (See SEMITIC LANGUAGES.)

CHALICE (through a central O. Fr. form of the Lat. _calix_, _calicis_, cup), a drinking-vessel of the cup or goblet form, now only used of the cup used in the celebration of the Eucharist (q.v.). For the various forms which the "chalice" so used has taken, see DRINKING-VESSELS and PLATE. When, in the eucharistic service, water is mixed with the wine, the "chalice" is known as the "mixed chalice." This has been customary both in the Eastern and Western Churches from early times. The Armenian Church does not use the "mixed chalice." It was used in the English Church before the Reformation. According to the present law of the English Church, the mixing of the water with wine is lawful, if this is not done as part of or during the services, i.e. if it is not done ceremonially (_Martin_ v. _Mackonochie_, 1868, L.R. 2 P.C. 365; _Read_ v. _Bp. of Lincoln_, 1892, A.C. 664).

CHALIER, JOSEPH (1747-1793), French Revolutionist. He was destined by his family for the church, but entered business, and became a partner in a firm at Lyons for which he travelled in the Levant, in Italy, Spain and Portugal. He was in Paris in 1789, and entered into relations with Marat, Camille Desmoulins and Robespierre. On his return to Lyons, Chalier was the first to be named member of the municipal bureau. He organized the national guard, applied the civil constitution of the clergy, and regulated the finances of the city so as to tax the rich heavily and spare the poor. Denounced to the Legislative Assembly by the directory of the department of Rhone-et-Loire for having made a nocturnal domiciliary perquisition, he was sent to the bar of the Assembly, which approved of his conduct. In the election for mayor of Lyons, in November 1792, he was defeated by a Royalist. Then Chalier became the orator and leader of the Jacobins of Lyons, and induced the other revolutionary clubs and the commune of his city to arrest a great number of Royalists in the night of the 5th and 6th of February 1793. The mayor, supported by the national guard, opposed this project. Chalier demanded of the Convention the establishment of a revolutionary tribunal and the levy of a revolutionary army at Lyons. The Convention refused, and the anti-revolutionary party, encouraged by this refusal, took action. On the 29th and 30th of May 1793 the sections rose; the Jacobins were dispossessed of the municipality and Chalier arrested. On the 15th of July, in spite of the order of the Convention, he was brought before the criminal tribunal of the Rhone-et-Loire, condemned to death, and guillotined the next day. The Terrorists paid a veritable worship to his memory, as to a martyr of Liberty.

See N. Wahl, "Etude sur Chalier," in _Revue historique_, t. xxxiv.; and _Les Premieres Annees de la Revolution a Lyon_ (Paris, 1894).

CHALK, the name given to any soft, pulverulent, pure white limestone. The word is an old one, having its origin in the Saxon _cealc_, and the hard form "kalk" is still in use amongst the country folk of Lincolnshire. The German _Kalk_ comprehends all forms of limestone; therefore a special term, _Kreide_, is employed for chalk--French _craie_. From being used as a common name, denoting a particular material, the word was subsequently utilized by geologists as an appellation for the _Chalk formation_; and so prominent was this formation in the eyes of the earlier workers that it imposed its name upon a whole system of rocks, the Cretaceous (Lat. _creta_, chalk), although this rock itself is by no means generally characteristic of the system as a whole.

The Chalk formation, in addition to the typical chalk material--_creta scriptoria_--comprises several variations; argillaceous kinds--_creta marga_ of Linnaeus--known locally as malm, marl, clunch, &c.; and harder, more stony kinds, called rag, freestone, rock, hurlock or harrock in different districts. In certain parts of the formation layers of nodular flints (q.v.) abound; in parts, it is inclined to be sandy, or to contain grains of glauconite which was originally confounded with another green mineral, chlorite, hence the name "chloritic marl" applied to one of the subdivisions of the chalk. In its purest form chalk consists of from 95 to 99% of calcium carbonate (carbonate of lime); in this condition it is composed of a mass of fine granular particles held together by a somewhat feeble calcareous cement. The particles are mostly the broken tests of foraminifera, along with the debris of echinoderm and molluscan shells, and many minute bodies, like coccoliths, of somewhat obscure nature.

The earliest attempts at subdivision of the Chalk formation initiated by Wm. Phillips were based upon lithological characters, and such a classification as "Upper Chalk with Flints," "Lower Chalk without Flints," "Chalk marl or Grey chalk," was generally in use in England until W. Whitaker established the following order in 1865:--

Upper Chalk, with flints

/ chalk rock Lower Chalk < chalk with few flints \ chalk without flints

Chalk Marl / Totternhoe stone \ " marl

In France, a similar system of classification was in vogue, the subdivisions being _craie blanche_, _craie tufan_, _craie chloritee_, until 1843 when d'Orbigny proposed the term _Senonien_ for the Upper Chalk and _Turonien_ for the Lower; later he divided the _Turonien_, giving the name _Cenomanien_ to the lower portion. The subdivisions of d'Orbigny were based upon the fossil contents and not upon the lithological characters of the rocks. In 1876 Prof. Ch. Barrois showed how d'Orbigny's classification might be applied to the British chalk rocks; and this scheme has been generally adopted by geologists, although there is some divergence of opinion as to the exact position of the base line of the Cenomanian.

The accompanying table shows the classification now adopted in England, with the zonal fossils and the continental names of the substages:--

+-----------------------------------------------+---------------------+----------+-----------+ | | |N. France | S.E. and | | Zonal fossils used in Britain. | Stages. | and | S. France.| | | | Belgium.*| | +-----------------------------------------------+---------------------+----------+-----------+ | / _Ostrea lunata_ (Norfolk) | Danian? | | | | | | (Trimingham) | | | | | _Belemnitella mucronata_ | | | | |A.< _Actinocamax quadratus_ | Upper Chalk | | | | | = _Inoceramus lingua_ in Yorkshire | Senonian | Flint- | | | | / _Marsupites_,| _Craie blanche_ | bearing | | | \ _Marsupites testudinarium_ \ _Uintacrinus_| | chalk. | | | | | | Marls, | | / _Micraster cor-anguinum_ | | | sandstones| |B.< " _cor-testudinarium_ | | | and | | \ _Holaster planus_, Chalk rock | | | limestones| +-----------------------------------------------+---------------------+ | (not | | _Terebratulina gracilis_ | Middle Chalk | | chalky) | | | Turonian | | with | | _Rhynchonella Cuvieri_, Melbourne rock | _Craie marneuse_ | | _Hippur- | +-----------------------------------------------+---------------------+ | ites_. | | | Lower Chalk, | | | | | Chalk Marl and | | | | | Cambridge Greensand | Marly | | | _Actinocamax plenus_ | Cenomanian | chalk. | | | _Holaster subglobosus_, Totternhoe stone. | | | | | _Schloenbachia varians_. | _Craie glauconieuse_| | | +-----------------------------------------------+---------------------+----------+-----------+ * (See table in article CRETACEOUS SYSTEM,)

Since Prof. Barrois introduced the zonal system of subdivision (C. Evans had used a similar scheme six years earlier), our knowledge of the English chalk has been greatly increased by the work of Jukes-Browne and William Hill, and particularly by the laborious studies of Dr A.W. Rowe. Instead of employing the mixed assemblage of animals indicated as zone fossils in the table, A. de Grossouvre proposed a scheme for the north of France based upon ammonite faunas alone, which he contended would be of more general applicability (_Recherches sur la Craie Superieure_, Paris, 1901).

The Upper Chalk has a maximum thickness in England of about 1000 ft., but post-cretaceous erosion has removed much of it in many districts. It is more constant in character, and more typically chalky than the lower stages; flints are abundant, and harder nodular beds are limited to the lower portions, where some of the compact limestones are known as "chalk rock." The thickness of the Middle Chalk varies from about 100 to 240 ft.; flints become scarcer in descending from the upper to the lower portions. The whole is more compact than the upper stage, and nodular layers are more frequent--the "chalk rock" of Dorset and the Isle of Wight belong to this stage. At the base is the hard "Melbourne rock." The thickness of the Lower Chalk in England varies from 60 to 240 ft. This stage includes part of the "white chalk without flints," the "chalk marl," and the "grey chalk." The Totternhoe stone is a hard freestone found locally in this stage. The basement bed in Norfolk is a pure limestone, but very frequently it is marly with grains of sand and glauconite, and often contains phosphatic nodules; this facies is equivalent to the "Cambridge Greensand" of some districts and the "chloritic marl" of others. In Devonshire the Lower Chalk has become thin sandy calcareous series.

The chalk can be traced in England from Flamborough Head in Yorkshire, in a south-westerly direction, to the coast of Dorset; and it not only underlies the whole of the S.E. corner, where it is often obscured by Tertiary deposits, but it can be followed across the Channel into northern France. Rocks of the same age as the chalk are widespread (see CRETACEOUS SYSTEM); but the variety of limestone properly called by this name is almost confined to the Anglo-Parisian basin. Some chalk occurs in the great Cretaceous deposits of Russia, and in Kansas, Iowa, Nebraska and S. Dakota in the United States. Hard white chalk occurs in Ireland in Antrim, and on the opposite shore of Scotland in Mull and Morven.

_Economic Products of the Chalk._--Common chalk has been frequently used for rough building purposes, but the more important building stones are "Beer stone," from Beer Head in Devonshire, "Sutton stone" from a little north of Beer, and the "Totternhoe stone." It is burned for lime, and when mixed with some form of clay is used for the manufacture of cement; chalk marl has been used alone for this purpose. As a manure, it has been much used as a dressing for clayey land. Flints from the chalk are used for road metal and concrete, and have been employed in building as a facing for walls. Phosphatic nodules for manure have been worked from the chloritic marl and Cambridge Greensand, and to some extent from the Middle Chalk. The same material is worked at Ciply in Belgium and Picardy in France. Chalk is employed in the manufacture of carbonate of soda, in the preparation of carbon dioxide, and in many other chemical processes; also for making paints, crayons and tooth-powder. _Whiting_ or _Spanish white_, used to polish glass and metal, is purified chalk prepared by triturating common chalk with a large quantity of water, which is then decanted and allowed to deposit the finely-divided

## particles it holds in suspension.

_Chalk Scenery._--Where exposed at the surface, chalk produces rounded, smooth, grass-covered hills as in the Downs of southern England and the Wolds of Yorkshire and Lincolnshire. The hills are often intersected by clean-cut dry valleys. It forms fine cliffs on the coast of Kent, Yorkshire and Devonshire.

Chalk is employed medicinally as a very mild astringent either alone or more usually with other astringents. It is more often used, however, for a purely mechanical action, as in the preparation hydrargyrum cum creta. As an antacid its use has been replaced by other drugs.

_Black chalk_ or _drawing slate_ is a soft carbonaceous schist, which gives a black streak, so that it can be used for drawing or writing. _Brown chalk_ is a kind of umber. _Red chalk_ or _reddle_ is an impure earthy variety of haematite. _French chalk_ is a soft variety of steatite, a hydrated magnesium silicate.

The most comprehensive account of the British chalk is contained in the _Memoirs of the Geological Survey of the United Kingdom_, "The Cretaceous Rocks of Britain," vol. ii. 1903, vol. iii. 1904 (with bibliography), by Jukes-Browne and Hill. See also "The White Chalk of the English Coast," several papers in the _Proceedings of the Geologists' Association_, London, (1) Kent and Sussex, xvi. 1900, (2) Dorset, xvii., 1901, (3) Devon, xviii., 1903, (4) Yorkshire, xviii., 1904. (J. A. H.)

CHALKHILL, JOHN (fl. 1600?), English poet. Two songs by him are included in Izaak Walton's _Compleat Angler_, and in 1683 appeared "Thealma and Clearchus. A Pastoral History in smooth and easie Verse. Written long since by John Chalkhill, Esq., an Acquaintant and Friend of Edmund Spencer" (1683), with a preface written five years earlier by Walton. Another poem, "Alcilia, Philoparthens Loving Follie" (1595, reprinted in vol. x. of the _Jahrbuch des deutschen Shakespeare-Vereins_), was at one time attributed to him. Nothing further is known of the poet, but a person of his name occurs as one of the coroners for Middlesex in the later years of Queen Elizabeth's reign. Professor Saintsbury, who included _Thealma and Clearchus_ in vol. ii. of his _Minor Poets of the Caroline Period_ (Oxford, 1906), points out a marked resemblance between his work and that of William Chamberlayne.

CHALKING THE DOOR, a Scottish custom of landlord and tenant law. In former days the law was that "a burgh officer, in presence of witnesses, chalks the most patent door forty days before Whit Sunday, having made out an execution of 'chalking,' in which his name must be inserted, and which must be subscribed by himself and two witnesses." This ceremony now proceeds simply on the verbal order of the proprietor. The execution of chalking is a warrant under which decree of removal will be pronounced by the burgh court, in virtue of which the tenant may be ejected on the expiration of a charge of six days.

CHALLAMEL, JEAN BAPTISTE MARIUS AUGUSTIN (1818-1894), French historian, was born in Paris on the 18th of March 1818. His writings consist chiefly of popular works, which enjoyed great success. The value of some of his books is enhanced by numerous illustrations, e.g. _Histoire-musee de la Revolution francaise_, which appeared in 50 numbers in 1841-1842 (3rd ed., in 72 numbers, 1857-1858); _Histoire de la mode en France; la toilette des femmes depuis l'epoque gallo-romaine jusqu'a nos jours_ (1874, with 12 plates; new ed., 1880, with 21 coloured plates). His _Memoires du peuple francaise_ (1865-1873) and _La France et les Francais a travers les siecles_ (1882) at least have the merit of being among the first books written on the social history of France. In this sense Challamel was a pioneer, of no great originality, it is true, but at any rate of fairly wide information. He died on the 20th of October 1894.

CHALLEMEL-LACOUR, PAUL AMAND (1827-1896), French statesman, was born at Avranches on the 19th of May 1827. After passing through the Ecole Normale Superieure he became professor of philosophy successively at Pau and at Limoges. The _coup d'etat_ of 1851 caused his expulsion from France for his republican opinions. He travelled on the continent, and in 1856 settled down as professor of French literature at the Polytechnic of Zurich. The amnesty of 1859 enabled him to return to France, but a projected course of lectures on history and art was immediately suppressed. He now supported himself by his pen, and became a regular contributor to the reviews. On the fall of the Second Empire in September 1870 the government of national defence appointed him prefect of the department of the Rhone, in which capacity he had to suppress the Communist rising at Lyons. Resigning his post on the 5th of February 1871, he was in January 1872 elected to the National Assembly, and in 1876 to the Senate. He sat at first on the Extreme Left; but his philosophic and critical temperament was not in harmony with the recklessness of French radicalism, and his attitude towards political questions underwent a steady modification, till the close of his life saw him the foremost representative of moderate republicanism. During Gambetta's lifetime, however, Challemel-Lacour was one of his warmest supporters, and he was for a time editor of Gambetta's organ, the _Republique francaise_. In 1879 he was appointed French ambassador at Bern, and in 1880 was transferred to London; but he lacked the suppleness and command of temper necessary to a successful diplomatist. He resigned in 1882, and in February 1883 became minister of foreign affairs in the Jules Ferry cabinet, but retired in November of the same year. In 1890 he was elected vice-president of the Senate, and in 1893 succeeded Jules Ferry as its president. His influence over that body was largely due to his clear and reasoned eloquence, which placed him at the head of contemporary French orators. In 1893 he also became a member of the French Academy. He distinguished himself by the vigour with which he upheld the Senate against the encroachments of the chamber, but in 1895 failing health forced him to resign, and he died in Paris on the 26th of October 1896. He published a translation of A. Heinrich Ritter's _Geschichte der Philosophie_ (1861); _La Philosophie individualiste: etude sur Guillaume de Humboldt_ (1864); and an edition of the works of Madame d'Epinay (1869).

In 1897 appeared Joseph Reinach's edition of the _OEuvres oratoires de Challemel-Lacour_.

CHALLENGE (O. Fr. _chalonge, calenge_, &c., from Lat. _calumnia_, originally meaning trickery, from _calvi_, to deceive, hence a false accusation, a "calumny"), originally a charge against a person or a claim to anything, a defiance. The term is now particularly used of an invitation to a trial of skill in any contest, or to a trial by combat as a vindication of personal honour (see DUEL), and, in law, of the objection to the members of a jury allowed in a civil action or in a criminal trial (see JURY).

"CHALLENGER" EXPEDITION. The scientific results of several short expeditions between 1860 and 1870 encouraged the council of the Royal Society to approach the British government, on the suggestion of Sir George Richards, hydrographer to the admiralty, with a view to commissioning a vessel for a prolonged cruise for oceanic exploration. The government detailed H.M.S. "Challenger," a wooden corvette of 2306 tons, for the purpose. Captain (afterwards Sir) George Nares was placed in command, with a naval crew; and a scientific staff was selected by the society with Professor (afterwards Sir) C. Wyville Thomson as director. The staff included Mr (afterwards Sir) John Murray and Mr H.N. Moseley, biologists; Dr von Willemoes-Suhm, Commander Tizard, and Mr J.Y. Buchanan, chemist and geologist. A complete scheme of instructions was drawn up by the society. The "Challenger" sailed from Portsmouth in December 1872. For nearly a year the work of the expedition lay in the Atlantic, which was crossed several times. Teneriffe, the Bermudas, the Azores, Madeira, the Cape Verd Islands, Bahia and Tristan da Cunha were successively visited, and in October 1873 the ship reached Cape Town. Steering then south-east and east she visited the various islands between 45 deg. and 50 deg. S., and reached Kerguelen Island in January 1874. She next proceeded southward about the meridian of 80 deg. E. She was the first steamship to cross the Antarctic circle, but the attainment of a high southerly latitude was not an object of the voyage, and early in March the ship left the south polar regions and made for Melbourne. Extensive researches were now made in the Pacific. The route led by New Zealand, the Fiji Islands, Torres Strait, the Banda Sea, and the China Sea to Hong Kong. The western Pacific was then explored northward to Yokohama, after which the "Challenger" struck across the ocean by Honolulu and Tahiti to Valparaiso. She then coasted southward, penetrated the Straits of Magellan, touched at Montevideo, recrossed the Atlantic by Ascension and the Azores, and reached Sheerness in May 1876. This voyage is without parallel in the history of scientific research. The _"Challenger" Report_ was issued in fifty volumes (London, 1880-1895), mainly under the direction of Sir John Murray, who succeeded Wyville Thomson in this work in 1882. Specialists in every branch of science assisted in its production. The zoological collections alone formed the basis for the majority of the volumes; the deep-sea soundings and samples of the deposits, the chemical analysis of water samples, the meteorological, water-temperature, magnetic, geological, and botanical observations were fully worked out, and a summary of the scientific results, narrative of the cruise and indices were also provided.

See also Lord G. Campbell, _Log Letters from the "Challenger"_, (1876); W.J.J. Spry, _Cruise of H.M.S. "Challenger"_ (1876); Sir C. Wyville Thomson, _Voyage of the "Challenger," The Atlantic, Preliminary Account of General Results_ (1877); J.J. Wild, _At Anchor; Narrative of Experiences afloat and ashore during the Voyage of H.M.S. "Challenger"_ (1878); H.N. Moseley, _Notes by a Naturalist on the "Challenger"_ (1879).

CHALLONER, RICHARD (1691-1781), English Roman Catholic prelate, was born at Lewes, Sussex, on the 29th of September 1691. After the death of his father, who was a rigid Dissenter, his mother, left in poverty, lived with some Roman Catholic families. Thus it came about that he was brought up as a Roman Catholic, chiefly at the seat of Mr Holman at Warkworth, Northamptonshire, where the Rev. John Gother, a celebrated controversialist, officiated as chaplain. In 1704 he was sent to the English College at Douai, where he was ordained a priest in 1716, took his degrees in divinity, and was appointed professor in that faculty. In 1730 he was sent on the English mission and stationed in London. The controversial treatises which he published in rapid succession attracted much attention, particularly his _Catholic Christian Instructed_ (1737), which was prefaced by a witty reply to Dr Conyers Middleton's _Letters from Rome, showing an Exact Conformity between Popery and Paganism_. Middleton is said to have been so irritated that he endeavoured to put the penal laws in force against his antagonist, who prudently withdrew from London. In 1741 Challoner was raised to the episcopal dignity at Hammersmith, and nominated co-adjutor with right of succession to Bishop Benjamin Petre, vicar-apostolic of the London district, whom he succeeded in 1758. He resided principally in London, but was obliged to retire into the country during the "No Popery" riots of 1780. He died on the 12th of January 1781, and was buried at Milton, Berkshire. Bishop Challoner was the author of numerous controversial and devotional works, which have been frequently reprinted and translated into various languages. He compiled the _Garden of the Soul_ (1740 ?), which continues to be the most popular manual of devotion among English-speaking Roman Catholics, and he revised an edition of the Douai version of the Scriptures (1749-1750), correcting the language and orthography, which in many places had become obsolete. Of his historical works the most valuable is one which was intended to be a Roman Catholic antidote to Foxe's well-known martyrology. It is entitled _Memoirs of Missionary Priests and other Catholicks of both Sexes who suffered Death or Imprisonment in England on account of their Religion, from the year 1577 till the end of the reign of Charles II._ (2 vols. 1741, frequently reprinted). He also published anonymously, in 1745, the lives of English, Scotch and Irish saints, under the title of _Britannia Sancta_, an interesting work which has, however, been superseded by that of Alban Butler.

For a complete list of his writings see J. Gillow's _Bibl. Dict. of Eng. Cath._ i. 452-458; Barnard, _Life of R. Challoner_ (1784); Flanagan, _History of the Catholic Church in England_ (1857); there is also a critical history of Challoner by Rev. E. Burton.

CHALMERS, ALEXANDER (1750-1834), Scottish writer, was born in Aberdeen on the 29th of March 1759. He was educated as a doctor, but gave up this profession for journalism, and he was for some time editor of the _Morning Herald_. Besides editions of the works of Shakespeare, Beattie, Fielding, Johnson, Warton, Pope, Gibbon, Bolingbroke, he published _A General Biographical Dictionary_ in 32 vols.(1812-1817); a _Glossary to Shakspeare_ (1797); an edition of Steevens's Shakespeare (1809); and the _British Essayists_, beginning with the _Tatler_ and ending with the _Observer_, with biographical and historical prefaces and a general index. He died in London on the 19th of December 1834.

CHALMERS, GEORGE (1742-1825), Scottish antiquarian and political writer, was born at Fochabers, a village in the county of Moray, in 1742. His father, James Chalmers, was a grandson of George Chalmers of Pittensear, a small estate in the parish of Lhanbryde, now St Andrews-Lhanbryde, in the same county, possessed by the main line of the family from about the beginning of the 17th to the middle of the 18th century. After completing the usual course at King's College, Aberdeen, young Chalmers studied law in Edinburgh for several years. Two uncles on the father's side having settled in America, he visited Maryland in 1763, with the view, it is said, of assisting to recover a tract of land of some extent about which a dispute had arisen, and was in this way induced to commence practice as a lawyer at Baltimore, where for a time he met with much success. Having, however, espoused the cause of the Royalist party on the breaking out of the American War of Independence, he found it expedient to abandon his professional prospects in the New World, and return to his native country. For the losses he had sustained as a colonist he received no compensation, and several years elapsed before he obtained an appointment that placed him in a state of comfort and independence.

In the meantime Chalmers applied himself with great diligence and assiduity to the investigation of the history and establishment of the English colonies in North America; and enjoying free access to the state papers and other documents preserved among what were then termed the plantation records, he became possessed of much important information. His work entitled _Political Annals of the present United Colonies from their Settlement to the Peace of 1763_, 4to, London, 1780, was to have formed two volumes; but the second, which should have contained the period between 1688 and 1763, never appeared. The first volume, however, is complete in itself, and traces the original settlement of the different American colonies, and the progressive changes in their constitutions and forms of government as affected by the state of public affairs in the parent kingdom. Independently of its value as being compiled from original documents, it bears evidence of great research, and has been of essential benefit to later writers. Continuing his researches, he next gave to the world _An Estimate of the Comparative Strength of Britain during the Present and Four Preceding Reigns_, London, 1782, which passed through several editions. At length, in August 1786, Chalmers, whose sufferings as a Royalist must have strongly recommended him to the government of the day, was appointed chief clerk to the committee of privy council on matters relating to trade, a situation which he retained till his death in 1825, a period of nearly forty years. As his official duties made no great demands on his time, he had abundant leisure to devote to his favourite studies,--the antiquities and topography of Scotland having thenceforth special attractions for his busy pen.

Besides biographical sketches of Defoe, Sir John Davies, Allan Ramsay, Sir David Lyndsay, Churchyard and others, prefixed to editions of their respective works, Chalmers wrote a life of Thomas Paine, the author of the _Rights of Man_, which he published under the assumed name of Francis Oldys, A.M., of the University of Pennsylvania; and a life of Ruddiman, in which considerable light is thrown on the state of literature in Scotland during the earlier part of the last century. His life of Mary, Queen of Scots, in two 4to vols., was first published in 1818. It is founded on a MS. left by John Whitaker, the historian of Manchester; but Chalmers informs us that he found it necessary to rewrite the whole. The history of that ill-fated queen occupied much of his attention, and his last work, _A Detection of the Love-Letters lately attributed in Hugh Campbell's work to Mary Queen of Scots_, is an exposure of an attempt to represent as genuine some fictitious letters said to have passed between Mary and Bothwell which had fallen into deserved oblivion. In 1797 appeared his _Apology for the Believers in the Shakespeare Papers which were exhibited in Norfolk Street_, followed by other tracts on the same subject. These contributions to the literature of Shakespeare are full of curious matter, but on the whole display a great waste of erudition, in seeking to show that papers which had been proved forgeries might nevertheless have been genuine. Chalmers also took part in the Junius controversy, and in _The Author of Junius Ascertained, from a Concatenation of Circumstances amounting to Moral Demonstration_, Lond. 1817, 8vo, sought to fix the authorship of the celebrated letters on Hugh Boyd. In 1824 he published _The Poetical Remains of some of the Scottish Kings, now first collected_; and in the same year he edited and presented as a contribution to the Bannatyne Club _Robene and Makyne and the Testament of Cresseid, by Robert Henryson_. His political writings are equally numerous. Among them may be mentioned _Collection of Treaties between Great Britain and other Powers_, Lond. 1790, 2 vols. 8vo; _Vindication of the Privileges of the People in respect to the Constitutional Right of Free Discussion_, &c., Lond. 1796, 8vo, published anonymously; _A Chronological Account of Commerce and Coinage in Great Britain from the Restoration till 1810_, Lond. 1810, 8vo; _Opinions of Eminent Lawyers on various points of English Jurisprudence, chiefly concerning the Colonies, Fisheries, and Commerce of Great Britain_, Lond. 1814, 2 vols. 8vo; _Comparative Views of the State of Great Britain before and since the War_, Lond. 1817, 8vo.

But Chalmers's greatest work is his _Caledonia_, which, however, he did not live to complete. The first volume appeared in 1807, and is introductory to the others. It is divided into four books, treating successively of the Roman, the Pictish, the Scottish and the Scoto-Saxon periods, from 80 to 1306 A.D. In these we are presented, in a condensed form, with an account of the people, the language and the civil and ecclesiastical history, as well as the agricultural and commercial state of Scotland during the first thirteen centuries of our era. Unfortunately the chapters on the Roman period are entirely marred by the author's having accepted as genuine Bertram's forgery _De Situ Britanniae_; but otherwise his opinions on controverted topics are worthy of much respect, being founded on a laborious investigation of all the original authorities that were accessible to him. The second volume, published in 1810, gives an account of the seven south-eastern counties of Scotland--Roxburgh, Berwick, Haddington, Edinburgh, Linlithgow, Peebles and Selkirk--each of them being treated of as regards name, situation and extent, natural objects, antiquities, establishment as shires, civil history, agriculture, manufactures and trade, and ecclesiastical history. In 1824, after an interval of fourteen years, the third volume appeared, giving, under the same headings, a description of the seven south-western counties--Dumfries, Kirkcudbright, Wigtown, Ayr, Lanark, Renfrew and Dumbarton. In the preface to this volume the author states that the materials for the history of the central and northern counties were collected, and that he expected the work would be completed in two years, but this expectation was not destined to be realized. He had also been engaged on a history of Scottish poetry and a history of printing in Scotland. Each of them he thought likely to extend to two large quarto volumes, and on both he expended an unusual amount of enthusiasm and energy. He had also prepared for the press an elaborate history of the life and reign of David I. In his later researches he was assisted by his nephew James, son of Alexander Chalmers, writer in Elgin.

George Chalmers died in London on the 31st of May 1825. His valuable and extensive library he bequeathed to his nephew, at whose death in 1841 it was sold and dispersed. Chalmers was a member of the Royal and Antiquarian Societies of London, an honorary member of the Antiquarian Society of Scotland, and a member of other learned societies. In private life he was undoubtedly an amiable man, although the dogmatic tone that disfigures portions of his writings procured him many opponents. Among his avowed antagonists in literary warfare the most distinguished were Malone and Steevens, the Shakespeare editors; Mathias, the author of the _Pursuits of Literature_; Dr Jamieson, the Scottish lexicographer; Pinkerton, the historian; Dr Irving, the biographer of the Scottish poets; and Dr Currie of Liverpool, But with all his failings in judgment Chalmers was a valuable writer. He uniformly had recourse to original sources of information; and he is entitled to great praise for his patriotic and self-sacrificing endeavours to illustrate the history, literature and antiquities of his native country. (J. M'D.)

CHALMERS, GEORGE PAUL (1836-1878), Scottish painter, was born at Montrose, and studied at Edinburgh. His landscapes are now more valued than the portraits which formed his earlier work. The best of these are "The End of the Harvest" (1873), "Running Water" (1875), and "The Legend" (in the National Gallery, Edinburgh). He became an associate (1867) and a full member (1871) of the Scottish Academy.

CHALMERS, JAMES (1841-1901), Scottish missionary to New Guinea, was born at Ardrishaig in Argyll. After serving in the Glasgow City Mission he passed through Cheshunt College, and, being accepted by the London Missionary Society, was appointed to Rarotonga in the South Pacific in 1866. Here the natives gave him the well-known name "Tamate." After ten years' service, especially in training native evangelists, he was transferred to New Guinea. In addition to his enthusiastic but sane missionary work, Chalmers did much to open up the island, and, with his colleague W.G. Lawes, gave valuable aid in the British annexation of the south-east coast of the island. On the 8th of April 1901, in company with a brother missionary, Oliver Tomkins, he was killed by cannibals at Goaribari Island. R.L. Stevenson has left on record his high appreciation of Chalmers's character and work.

Chalmers's _Autobiography and Letters_ were edited by Richard Lovett in 1902, who also wrote a popular life called _Tamate_.

CHALMERS, THOMAS (1780-1847), Scottish divine, was born at Anstruther in Fifeshire, on the 17th of March 1780. At the age of eleven he was entered as a student at St Andrews, where he devoted himself almost exclusively to mathematics. In January 1799 he was licensed as a preacher of the Gospel by the St Andrews presbytery. In May 1803, after attending further courses of lectures in Edinburgh, and acting as assistant to the professor of mathematics at St Andrews, he was ordained as minister of Kilmany in Fifeshire, about 9 m. from the university town, where he continued to lecture. His mathematical lectures roused so much enthusiasm that they were discontinued by order of the authorities, who disliked the disturbance of the university routine which they involved. Chalmers then opened mathematical classes on his own account which attracted many students; at the same time he delivered a course of lectures on chemistry, and ministered to his parish at Kilmany. In 1805 he became a candidate for the vacant professorship of mathematics at Edinburgh, but was unsuccessful. In 1808 he published an _Inquiry into the Extent and Stability of National Resources_, a contribution to the discussion created by Bonaparte's commercial policy. Domestic bereavements and a severe illness then turned his thoughts in another direction. At his own request the article on Christianity was assigned to him in Dr Brewster's _Edinburgh Encyclopaedia_, and in studying the credentials of Christianity he received a new impression of its contents. His journal and letters show how he was led from a sustained effort to attain the morality of the Gospel to a profound spiritual revolution. After this his ministry was marked by a zeal which made it famous. The separate publication of his article in the _Edinburgh Encyclopaedia_, and contributions to the _Edinburgh Christian Instructor_ and the _Eclectic Review_, enhanced his reputation as an author. In 1815 he became minister of the Tron Church, Glasgow, in spite of determined opposition to him in the town council on the ground of his evangelical teaching. From Glasgow his repute as a preacher spread throughout the United Kingdom. A series of sermons on the relation between the discoveries of astronomy and the Christian revelation was published in January 1817, and within a year nine editions and 20,000 copies were in circulation. When he visited London Wilberforce wrote, "all the world is wild about Dr Chalmers."

In Glasgow Chalmers made one of his greatest contributions to the life of his own time by his experiments in parochial organization. His parish contained about 11,000 persons, and of these about one-third were unconnected with any church. He diagnosed this evil as being due to the absence of personal influence, spiritual oversight, and the want of parochial organizations which had not kept pace in the city, as they had done in rural parishes, with the growing population. He declared that twenty new churches, with parishes, should be erected in Glasgow, and he set to work to revivify, remodel and extend the old parochial economy of Scotland. The town council consented to build one new church, attaching to it a parish of 10,000 persons, mostly weavers, labourers and factory workers, and this church was offered to Dr Chalmers that he might have a fair opportunity of testing his system.

In September 1819 he became minister of the church and parish of St John, where of 2000 families more than 800 had no connexion with any Christian church. He first addressed himself to providing schools for the children. Two school-houses with four endowed teachers were established, where 700 children were taught at the moderate fees of 2s. and 3s. per quarter. Between 40 and 50 local Sabbath schools were opened, where more than 1000 children were taught the elements of secular and religious education. The parish was divided into 25 districts embracing from 60 to 100 families, over each of which an elder and a deacon were placed, the former taking oversight of their spiritual, the latter of their physical needs. Chalmers was the mainspring of the whole system, not merely superintending the visitation, but personally visiting all the families, and holding evening meetings, when he addressed those whom he had visited. This parochial machinery enabled him to make a singularly successful experiment in dealing with the problem of poverty. At this time there were not more than 20 parishes north of the Forth and Clyde where there was a compulsory assessment for the poor, but the English method of assessment was rapidly spreading. Chalmers believed that compulsory assessment ended by swelling the evil it was intended to mitigate, and that relief should be raised and administered by voluntary means. His critics replied that this was impossible in large cities. When he undertook the management of the parish of St John's, the poor of the parish cost the city L1400 per annum, and in four years, by the adoption of his method, the pauper expenditure was reduced to L280 per annum. The investigation of all new applications for relief was committed to the deacon of the district, and every effort was made to enable the poor to help themselves. When once the system was in operation it was found that a deacon, by spending an hour a week among the families committed to his charge, could keep himself acquainted with their character and condition.

In 1823, after eight years of work at high pressure, he was glad to accept the chair of moral philosophy at St Andrews, the seventh academic offer made to him during his eight years in Glasgow. In his lectures he excluded mental philosophy and included the whole sphere of moral obligation, dealing with man's duty to God and to his fellow-men in the light of Christian teaching. Many of his lectures are printed in the first and second volumes of his published works. In ethics he made contributions to the science in regard to the place and functions of volition and attention, the separate and underived character of the moral sentiments, and the distinction between the virtues of perfect and imperfect obligation. His lectures kindled the religious spirit among his students, and led some of them to devote themselves to missionary effort. In November 1828 he was transferred to the chair of theology in Edinburgh. He then introduced the practice of following the lecture with a viva voce examination on what had been delivered. He also introduced text-books, and came into stimulating contact with his people; perhaps no one has ever succeeded as he did by the use of these methods in communicating intellectual, moral and religious impulse to so many students.

These academic years were prolific also in a literature of various kinds. In 1826 he published a third volume of the _Christian and Civic Economy of Large Towns_, a continuation of work begun at St John's, Glasgow. In 1832 he published a _Political Economy_, the chief purpose of which was to enforce the truth that the right economic condition of the masses is dependent on their right moral condition, that character is the parent of comfort, not vice versa. In 1833 appeared a treatise on _The Adaptation of External Nature to the Moral and Intellectual Constitution of Man_. In 1834 Dr Chalmers was elected fellow of the Royal Society of Edinburgh, and in the same year he became corresponding member of the Institute of France; in 1835 Oxford conferred on him the degree of D.C.L. In 1834 he became leader of the evangelical section of the Scottish Church in the General Assembly. He was appointed chairman of a committee for church extension, and in that capacity made a tour through a large part of Scotland, addressing presbyteries and holding public meetings. He also issued numerous appeals, with the result that in 1841, when he resigned his office as convener of the church extension committee, he was able to announce that in seven years upwards of L300,000 had been contributed, and 220 new churches had been built. His efforts to induce the Whig government to assist in this effort were unsuccessful.

In 1841 the movement which ended in the Disruption was rapidly culminating, and Dr Chalmers found himself at the head of the party which stood for the principle that "no minister shall be intruded into any parish contrary to the will of the congregation" (see FREE CHURCH OF SCOTLAND). Cases of conflict between the church and the civil power arose in Auchterarder, Dunkeld and Marnoch; and when the courts made it clear that the church, in their opinion, held its temporalities on condition of rendering such obedience as the courts required, the church appealed to the government for relief. In January 1843 the government put a final and peremptory negative on the church's claims for spiritual independence. On the 18th of May 1843 470 clergymen withdrew from the general assembly and constituted themselves the Free Church of Scotland, with Dr Chalmers as moderator. He had prepared a sustentation fund scheme for the support of the seceding ministers, and this was at once put into successful operation. On the 30th of May 1847, immediately after his return from the House of Commons, where he had given evidence as to the refusal of sites for Free Churches by Scottish landowners, he was found dead in bed.

Dr Chalmers' action throughout the Free Church controversy was so consistent in its application of Christian principle and so free from personal or party animus, that his writings are a valuable source for argument and illustration on the question of Establishment. "I have no veneration," he said to the royal commissioners in St Andrews, before either the voluntary or the non-intrusive controversies had arisen, "for the Church of Scotland _qua_ an establishment, but I have the utmost veneration for it _qua_ an instrument of Christian good." He was transparent in character, chivalrous, kindly, firm, eloquent and sagacious; his purity of motive and unselfishness commanded absolute confidence; he had originality and initiative in dealing with new and difficult circumstances, and great aptitude for business details.

During a life of incessant activity Chalmers scarcely ever allowed a day to pass without its modicum of composition; at the most unseasonable times, and in the most unlikely places, he would occupy himself with literary work. His writings occupy more than 30 volumes. He would have stood higher as an author had he written less, or had he indulged less in that practice of reiteration into which he was constantly betrayed by his anxiety to impress his ideas upon others. As a political economist he was the first to unfold the connexion that subsists between the degree of the fertility of the soil and the social condition of a community, the rapid manner in which capital is reproduced (see Mill's _Political Economy_, i. 94), and the general doctrine of a limit to all the modes by which national wealth may accumulate. He was the first also to advance that argument in favour of religious establishments which meets upon its own ground the doctrine of Adam Smith, that religion like other things should be left to the operation of the natural law of supply and demand. In the department of natural theology and the Christian evidences he ably advocated that method of reconciling the Mosaic narrative with the indefinite antiquity of the globe which William Buckland (1784-1856) advanced in his Bridgewater Treatise, and which Dr Chalmers had previously communicated to him. His refutation of Hume's objection to the truth of miracles is perhaps his intellectual _chef-d'oeuvre_. The distinction between the laws and dispositions of matter, as between the ethics and objects of theology, he was the first to indicate and enforce, and he laid great emphasis on the superior authority as witnesses for the truth of Revelation of the Scriptural as compared with the Extra-Scriptural writers, and of the Christian as compared with the non-Christian testimonies. In his _Institutes of Theology_, no material modification is attempted on the doctrines of Calvinism, which he received with all simplicity of faith as revealed in the Divine word, and defended as in harmony with the most profound philosophy of human nature and of the Divine providence.

For biographical details see Dr W. Hanna's _Memoirs_ (Edinburgh, 4 vols., 1849-1852); there is a good short _Life_ by Mrs Oliphant (1893). (W. Ha.; D. Mn.)

CHALONER, SIR THOMAS (1521-1565), English statesman and poet, was the son of Roger Chaloner, mercer of London, a descendant of the Denbighshire Chaloners. No details are known of his youth except that he was educated at both Oxford and Cambridge. In 1540 he went, as secretary to Sir Henry Knyvett, to the court of Charles V., whom he accompanied in his expedition against Algiers in 1541, and was wrecked on the Barbary coast. In 1547 he joined in the expedition to Scotland, and was knighted, after the battle of Musselburgh, by the protector Somerset, whose patronage he enjoyed. In 1549 he was a witness against Dr Bonner, bishop of London; in 1551 against Stephen Gardiner, bishop of Winchester; in the spring of the latter year he was sent as a commissioner to Scotland, and again in March 1552. In 1553 he went with Sir Nicholas Wotton and Sir William Pickering on an embassy to France, but was recalled by Queen Mary on her accession. In spite of his Protestant views, Chaloner was still employed by the government, going to Scotland in 1555-1556, and providing carriages for troops in the war with France, 1557-1558. In 1558 he went as Elizabeth's ambassador to the emperor Ferdinand at Cambrai, from July 1559 to February 1559/60 he was ambassador to King Philip at Brussels, and in 1561 he went in the same capacity to Spain. His letters are full of complaints of his treatment there, but it was not till 1564, when in failing health, that he was allowed to return home. He died at his house in Clerkenwell on the 14th of October 1565. He acquired during his years of service three estates, Guisborough in Yorkshire, Steeple Claydon in Buckinghamshire, and St Bees in Cumberland. He married (1) Joan, widow of Sir Thomas Leigh; and (2) Etheldreda, daughter of Edward Frodsham, of Elton, Cheshire, by whom he had one son, Sir Thomas Chaloner (1561-1615), the naturalist. Chaloner was the intimate of most of the learned men of his day, and with Lord Burghley he had a life-long friendship. Throughout his busy official life he occupied himself with literature, his Latin verses and his pastoral poems being much admired by his contemporaries. Chaloner's "Howe the Lorde Mowbray ... was ... banyshed the Realme," printed in the 1559 edition of William Baldwin's _Mirror for Magistrates_ (repr. in vol. ii. pt. 1 of Joseph Haslewood's edition of 1815), has sometimes been attributed to Thomas Churchyard. His most important work, _De Rep. Anglorum instauranda libri decem_, written while he was in Spain, was first published by William Malim (1579, 3 pts.), with complimentary Latin verses in praise of the author by Burghley and others. Chaloner's epigrams and epitaphs were also added to the volume, as well as _In laudem Henrici octavi ... carmen Panegericum_, first printed in 1560. Amongst his other works are _The praise of folie, Moriae encomium_ ... by Erasmus ... Englished by Sir Thomas Chaloner, Knight (1549, ed. Janet E. Ashbee, 1901); _A book of the Office of Servantes_ (1543), translated from Gilbert Cognatus; and _An homilie of Saint John Chrysostome_.... Englished by T.C. (1544).

See "The Chaloners, Lords of the Manor of St Bees," by William Jackson, in _Transactions of the Cumberland Assoc. for the Advancement of Literature and Science_, pt. vi. pp. 47-74, 1880-1881.

CHALONS-SUR-MARNE, a town of north-eastern France, capital of the department of Marne, 107 m. E. of Paris on the main line of the Eastern railway to Nancy, and 25 m. S.S.E. of Reims. Pop. (1906) 22,424. Chalons is situated in a wide level plain principally on the right bank of the Marne, its suburb of Marne, which contains the railwaystations of the Eastern and Est-Etat railways, lying on the left bank. The town proper is bordered on the west by the lateral canal of the Marne, across which lies a strip of ground separating it from the river itself. Chalons is traversed by branches of the canal and by small streams, and its streets are for the most part narrow and irregular, but it is surrounded by ample avenues and promenades, the park known as the Jard, in the south-western quarter, being especially attractive. Huge barracks lie to the north and east. There are several interesting churches in the town. The cathedral of St Etienne dates chiefly from the 13th century, but its west facade is in the classical style and belongs to the 17th century. There are stained-glass windows of the 13th century in the north transept. Notre-Dame, of the 12th and 13th centuries, is conspicuous for its four Romanesque towers, two flanking the apse; the other two, surmounted by tall lead spires, flanking the principal facade. The churches of St. Alpin, St Jean and St Loup date from various periods between the 11th and the 17th centuries. The hotel-de-ville (1771), facing which stands a monument to President Carnot; the prefecture (1750-1764), once the residence of the intendants of Champagne; the college, once a Jesuit establishment; and a training college which occupies the Augustinian abbey of Toussaints (16th and 17th centuries), are noteworthy civil buildings. The houses of Chalons are generally ill-built of timber and plaster, or rough-cast, but some old mansions, dating from the 15th to the 16th centuries, remain. The church of Ste Pudentienne, on the left bank of the river, is a well-known place of pilgrimage. The town is the seat of a bishop and a prefect, and headquarters of the VI. army corps; it has tribunals of first instance and of commerce, a chamber of commerce, a board of trade-arbitrators, a museum, a library, training colleges, a higher ecclesiastical seminary, a communal college and an important technical school. The principal industry is brewing, which is carried on in the suburb of Marne. Galleries of immense length, hewn in a limestone hill and served by lines of railway, are used as store-houses for beer. The preparation of champagne, the manufacture of boots and shoes, brushes, wire-goods and wall-paper also occupy many hands. There is trade in cereals.

Chalons-sur-Marne occupies the site of the chief town of the Catalauni, and some portion of the plains which lie between it and Troyes was the scene of the defeat of Attila in the conflict of 451. In the 10th and following centuries it attained great prosperity as a kind of independent state under the supremacy of its bishops, who were ecclesiastical peers of France. In 1214 the militia of Chalons served at the battle of Bouvines; and in the 15th century the citizens maintained their honour by twice (1430 and 1434) repulsing the English from their walls. In the 16th century the town sided with Henry IV., king of France, who in 1589 transferred thither the parlement of Paris, which shortly afterwards burnt the bulls of Gregory XIV. and Clement VIII. In 1856 Napoleon III. established a large camp, known as the Camp of Chalons, about 16 m. north of the town by the railway to Reims. It was situated in the immediate neighbourhood of Grand Mourmelon and Petit Mourmelon, and occupied an area of nearly 30,000 acres. The "Army of Chalons," formed by Marshal MacMahon in the camp after the first reverses of the French in 1870, marched thence to the Meuse, was surrounded by the Germans at Sedan, and forced to capitulate. The camp is still a training-centre for troops.

About 5 m. E. of Chalons is L'Epine, where there is a beautiful pilgrimage church (15th and 16th centuries, with modern restoration) with a richly-sculptured portal. In the interior there is a fine choir-screen, an organ of the 16th century, and an ancient and much-venerated statue of the Virgin.

CHALON-SUR-SAONE, a town of east-central France, capital of an arrondissement in the department of Saone-et-Loire, 81 m. N. of Lyons by the Paris-Lyon railway. Pop. (1906) 26,538. It is a well-built town, with fine quays, situated in an extensive plain on the right bank of the Saone at its junction with the Canal du Centre. A handsome stone bridge of the 15th century, decorated in the 18th century with obelisks, connects it with the suburb of St Laurent on an island in the river. The principal building is the church of St Vincent, once the cathedral. It dates mainly from the 12th to the 15th centuries, but the facade is modern and unpleasing. The old bishop's palace is a building of the 15th century. The church of St Pierre, with two lofty steeples, dates from the late 17th century. Chalon preserves remains of its ancient ramparts and a number of old houses. The administrative buildings are modern. An obelisk was erected in 1730 to commemorate the opening of the canal. There is a statue of J.N. Niepce, a native of the town. Chalon is the seat of a sub-prefect and a court of assizes, and there are tribunals of first instance and commerce, a branch of the Bank of France, a chamber of commerce, communal colleges for boys and girls, a school of drawing, a public library and a museum. Chalon ranks next to Le Creusot among the manufacturing towns of Burgundy; its position at the junction of the Canal du Centre and the Saone, and as a railway centre for Lyons, Paris, Dole, Lons-le-Saunier and Roanne, brings it a large transit trade. The founding and working of copper and iron is its main industry; the large engineering works of Petit-Creusot, a branch of those of Le Creusot, construct bridges, tug-boats and torpedo-boats; distilleries, glass-works, chemical works, straw-hat manufactories, oil-works, tile-works and sugar refineries also occupy many hands. Wine, grain, iron, leather and timber are among the many products for which the town is an entrepot. About 2 m. east of Chalon is St Marcel (named after the saint who in the 2nd century preached Christianity at Chalon), which has a church of the 12th century, once belonging to a famous abbey.

Chalon-sur-Saone is identified with the ancient _Cabillonum_, originally an important town of the Aedui. It was chosen in the 6th century by Gontram, king of Burgundy, as his capital; and it continued till the 10th to pay for its importance by being frequently sacked. The bishopric, founded in the 4th century, was suppressed at the Revolution. In feudal times Chalon was the capital of a countship. In 1237 it was given in exchange for other fiefs in the Jura by Jean le Sage, whose descendants nevertheless retained the title. Hugh IV., duke of Burgundy, the other party to the exchange, gave the citizens a communal charter in 1256. In its modern history the most important event was the resistance offered to a division of the Austrian army in 1814.

CHALUKYA, the name of an Indian dynasty which ruled in the Deccan from A.D. 550 to 750, and again from 973 to 1190. The Chalukyas themselves claimed to be Rajputs from the north who imposed their rule on the Dravidian inhabitants of the Deccan tableland, and there is some evidence for connecting them with the Chapas, a branch of the foreign Gurjaras. The dynasty was founded by a chief named Pulakesin I., who mastered the town of Vatapi (now Badami, in the Bijapur district) about 550. His sons extended their principality east and west; but the founder of the Chalukya greatness was his grandson Pulakesin II., who succeeded in 608 and proceeded to extend his rule at the expense of his neighbours. In 609 he established as his viceroy in Vengi his brother Kubja Vishnuvardhana, who in 615 declared his independence and established the dynasty of Eastern Chalukyas, which lasted till 1070. In 620 Pulakesin defeated Harsha (q.v.), the powerful overlord of northern India, and established the Nerbudda as the boundary between the South and North. He also defeated in turn the Chola, Pandya and Kerala kings, and by 630 was beyond dispute the most powerful sovereign in the Deccan. In 642, however, his capital was taken and he himself killed by the Pallava king Narasimhavarman. In 655 the Chalukya power was restored by Pulakesin's son Vikramaditya I.; but the struggle with the Pallavas continued until, in 740, Vikramaditya II. destroyed the Pallava capital. In 750 Vikramaditya's son, Kirtivarman Chalukya, was overthrown by the Rashtrakutas.

In 973, Taila or Tailapa II. (d. 995), a scion of the royal Chalukya race, succeeded in overthrowing the Rashtrakuta king Kakka II., and in recovering all the ancient territory of the Chalukyas with the exception of Gujarat. He was the founder of the dynasty known as the Chalukyas of Kalyani. About A.D. 1000 a formidable invasion by the Chola king Rajaraja the Great was defeated, and in 1052 Somesvara I., or Ahamavalla (d. 1068), the founder of Kalyani, defeated and slew the Chola Rajadhiraja. The reign of Vikramaditya VI., or Vikramanka, which lasted from 1076 to 1126, formed another period of Chalukya greatness. Vikramanka's exploits against the Hoysala kings and others, celebrated by the poet Bilhana, were held to justify him in establishing a new era dating from his accession. With his death, however, the Chalukya power began to decline. In 1156 the commander-in-chief Bijjala (or Vijjana) Kalachurya revolted, and he and his sons held the kingdom till 1183. In this year Somesvara IV. Chalukya recovered part of his patrimony, only to succumb, about 1190, to the Yadavas of Devagiri and the Hoysalas of Dorasamudra. Henceforth the Chalukya rajas ranked only as petty chiefs.

See J.F. Fleet, _Dynasties of the Kanarese Districts_; Prof. R.G. Bhandarker, "Early History of the Deccan," in the _Bombay Gazetteer_ (1896), vol. i.