part 2

, 1568. 13.

=Description=—Couch-grass has a long, stiff, pale yellow, smooth rhizome, ⅒ of an inch in diameter, creeping close under the surface of the ground, occasionally branching, marked at intervals of about an inch by nodes, which bear slender branching roots and the remains of sheathing rudimentary leaves.

As found in the shops, the rhizome is always free from rootlets, cut into short lengths of ⅛ to ¼ of an inch, and dried. It is thus in the form of little, shining, straw-coloured, many-edged, tubular pieces, which are without odour, but have a slightly sweet taste.

=Microscopic Structure=—A transverse section of this rhizome shows two different portions of tissue, separated by the so-called nucleus-sheath. The latter consists of an unbroken ring of prismatic cells, analogous to those occurring in sarsaparilla. In _Rhizoma Graminis_, the outer part of the tissue exhibits a diffuse circle of about 20 liber bundles, and the interior part about the same number of fibro-vascular bundles more densely packed. The pith is reduced to a few rows of cells, the rhizome being always hollow, except at the nodes. No solid contents are to be met with in the tissue.

_Chemical Composition_—The constituents of couch-grass include no substance to which medicinal powers can be ascribed. The juice of the rhizome afforded to H. Müller[2722] about 3 per cent. of sugar, and 7 to 8 per cent. of _Triticin_, C₁₂H₂₂O₁₁, a tasteless, amorphous, gummy substance, easily transformed into sugar if its concentrated solution is kept for a short time at 110°C. When treated with nitric acid, it yields oxalic acid. The rhizome affords also another gummy matter containing nitrogen, and quickly undergoing decomposition; the drug moreover is somewhat rich in acid malates. Mannite is probably occasionally present as in taraxacum (p. 394), for such is the inference we draw from the opposite results obtained by Stenhouse and by Völcker. Starch, pectin and resin are wanting. The rhizome leaves 4½ per cent. of ash.

=Uses=—A decoction of the rhizome has of late been recommended in mucous discharge from the bladder.

=Substitutes=—_Agropyrum acutum_ R. et S., _A. pungens_ R. et S., and _A. junceum_ P. Beauv., by some botanists regarded as mere maritime varieties of _A. repens_, have rootstocks perfectly similar to this latter.

_Cynodon Dactylon_ Pers., a grass very common in the South of Europe and the warmer parts of Western Europe, also indigenous to Northern Africa as far as Sennaar and Abyssinia, affords the _Gros Chiendent_ or _Chiendent pied-de-poule_ of the French. It is a rhizome differing from that of couch-grass in being a little stouter. Under the microscope it displays an entirely different structure, inasmuch as it contains a large number of much stronger fibro-vascular bundles, and a cellular tissue loaded with starch, and is therefore in appearance much more woody. It thus approximates to the rhizome of _Carex arenaria_ L., which is as much used in Germany as that of _Cynodon_ in Southern Europe. The latter appears to contain _Asparagin_ (the _Cynodin_ of Semmola[2723]), or a substance similar to it.

[2722] _Archiv der Pharm._ 203. (1873) 17.

[2723] Della Cinodina, nuovo prodotto organico, trovato nella gramigna officinale, _Cynodon Dactylon_.—_Opere minori di Giovanni Semmola_, Napoli, 1841.—Abstracted in the _Jahresbericht_ of Berzelius, Tübingen, 1845. 535.

_II.—CRYPTOGAMOUS_ OR _FLOWERLESS PLANTS._

=_Vascular Cryptogams._=

LYCOPODIACEÆ.

SPORÆ LYCOPODII.

_Lycopodium_; _Semen vel Sporulæ Lycopodii_; F. _Lycopode_; G. _Bärlappsamen_, _Hexenmehl_.

=Botanical Origin=—_Lycopodium clavatum_ L.—This plant, the Common Clubmoss, is almost cosmopolitan. It is found on hilly pastures and heaths throughout Central and Northern Europe from the Alps and Pyrenees to the Arctic reunions, in the mountains of the east and centre of Spain, throughout Russian Asia to Amurland and Japan, in North and South America, the Falkland Isles, Australia and the Cape of Good Hope. It occurs throughout Great Britain, but is most plentiful on the moors of the northern counties.

The part of the plant employed in pharmacy is the minute spores, which, as a yellow powder, are shaken out of the kidney-shaped capsules or sporangia, growing on the inner side of the bracts covering the fruit-spike.

The manner in which those sporæ are able to reproduce the mother plant is not yet satisfactorily ascertained.[2724]

=History=—The Common Clubmoss was well known as _Muscus terrestris_ or _Muscus clavatus_, to the older botanists, as Tragus, Dodonæus, Tabernæmontanus, Bauhin, Parkinson and Ray, by most of whom its supposed virtues as a herb have been commemorated. Though the powder (spores) was officinal in Germany, and used as an application to wounds in the middle of the 17th century,[2725] it does not appear to have been known in the English shops until a comparatively recent period. It is not included by Dale[2726] in the list of drugs sold by London druggists in 1692, nor enumerated in English drug lists of the last century; and it never had a place in the London Pharmacopœia.

[2724] The few particulars may be found in the excellent description of Lycopodium in Luerssen’s “_Medicinisch-pharmaceutische Botanik_,” i. (Leipzig, 1878) 635, with figures.

[2725] Schröder, _Pharmacopœia Medico-chymica_, ed. 4, Lugd. 1656. 538.—Flückiger, “_Documente_” (quoted p. 404) 63. 68.

[2726] _Pharmacologia_, Lond. 1693.

=Description=—Lycopodium is a fine, mobile, inodorous, tasteless powder of pale yellow hue, having at 16° C. a sp. gr. of 1·062. It floats on water and is wetted with difficulty, yet sinks in that fluid after boiling. By strong titration it coheres, assumes a grey tint, and leaves an oily stain on paper; it may then be mixed with water. It is immediately moistened by oily and alcoholic liquids, chloroform, or ether. It loses only 4 per cent. of moisture when dried at 100° C. When slowly heated, it burns away quietly, but when projected into flame, it ignites instantly and explosively, burning with much light, an effect exhibited by some other pulverulent bodies having a peculiar structure, as fern spores and kamala.

=Microscopic Structure=—Under the microscope lycopodium is seen to be composed of uniform cells or granules, 25 mkm. in diameter, each bounded by four faces, one of which (the base) is convex, while the others terminate in a triangular pyramid, the three furrowed edges of which do not reach quite to the base. These tetrahedral granules are marked by minute ridges, forming by their intersections, regular five- or six-sided meshes. At the points of intersection, small elevations are produced, which, under a low magnifying power, give the granules a speckled appearance. Below this network lies a yellow, coherent, thin, but compact membrane, which exhibits considerable power of resistance, not being ruptured either by boiling water or by potash lye. Oil of vitriol does not act upon it in the cold, even after several days; but it instantly penetrates the grains and renders them transparent, while at the same time numerous drops of oil make their appearance and quickly exude.

=Chemical Composition=—One of the most remarkable constituents of lycopodium spores is a fixed oil, which they contain to the astonishing amount of 47 per cent. Bucholz pointed out its existence in 1807, but obtained it only to the extent of 6 per cent. Yet if the spores are thoroughly comminuted by prolonged trituration with sand, and are then exhausted with chloroform or ether, we find that the larger proportion above mentioned can be obtained. The oil is a bland liquid, which does not solidify even at -15° C.

By subjecting lycopodium or its extract to distillation with or without an alkali, Stenhouse obtained volatile bases, the presence of which we can fully confirm; but they occur in exceedingly small proportion. The ash of lycopodium amounts to 4 per cent.; it is not alkaline; it contains alumina, and one per cent. of phosphoric acid, constituents likewise found in the green parts of the plant.

=Production and Commerce=—To obtain lycopodium, the tops of the plant are cut as the spikes approach maturity, taken home, and the powder shaken out and separated by a sieve. It is collected chiefly in July and August, in Russia, Germany and Switzerland. The quantity obtained varies greatly by reason of frequent failures in the growth of the plant.

France imported in 1870, 7262 kilo. (16,017 lb.) of lycopodium, chiefly from Germany. The consumption in England is probably very much smaller, but there are no data to consult.

=Uses=—Lycopodium is not now regarded as possessing any medicinal virtues, and is only used externally for dusting excoriated surfaces and for placing in pill boxes to prevent the mutual adhesion of pills. It is also employed by the pyrotechnist.

=Adulteration=—The spores are so peculiar in structure, that they can be distinguished with certainty by the microscope from all other substances. It is only the species of clubmoss that are nearly related to _L. clavatum_,[2727] that yield an analogous product, and this may be used with equal advantage.

The pollen of phænogamous plants, as of _Pinus silvestris_, looks at first sight much like lycopodium, but its structure is totally different and very easily recognized by the microscope.

Water, even on boiling, is unable to dissolve anything from lycopodium; slight traces of sulphate of calcium are not seldom met with in the filtrate. Yet an undue proportion of gypsum will be detected by the following methods:—

Starch and dextrin, which are sometimes fraudulently mixed with the spores, are easily recognized by the well-known tests. Inorganic admixtures, as gypsum or magnesia, may be detected by their sinking in bisulphide of carbon, whereas lycopodium rises to the surface; or by incineration, a good commercial drug leaving about 4 per cent. of ash.

FILICES.

RHIZOMA FILICIS.

_Radix Filicis maris_; _Male Fern Rhizome_, _Male Fern Root_; F. _Racine de Fougère mâle_; G. _Farnwurzel_.

=Botanical Origin=—_Aspidium Filix mas_ Swartz (_Polypodium_ L. _Nephrodium_ Michaux). The male fern is one of the most widely distributed species, usually growing in abundance and, in temperate regions, ascending as high as the arborescent vegetation. It occurs all over Europe from Sicily to Iceland, in Greenland, throughout Central and Russian Asia to the Himalaya and Japan; is found throughout China, and again in Java and the Sandwich Islands, as well as in Africa from Algeria to the Cape Colony and Mauritius. In North America it is wanting in the Eastern United States, being principally replaced by the nearly allied _Aspidium marginale_ Sw. and _A. Goldieanum_ Hook.; but it is met with in Canada, California and Mexico, as well as in New Granada, Venezuela, Brazil, and Peru.

=History=—The use of the rhizome of ferns as a vermifuge was well known to the ancients,[2728] as Theophrastus, Dioscorides and Pliny all giving curious descriptions of the plant. The remedy would appear to have been administered also during the middle ages, for it was again noticed by Valerius Cordus,[2729] and had a place in German pharmaceutical tariffs of the sixteenth century as well as in Schröder’s Dispensatory.[2730] Yet Tragus[2731] remarks that, at least in Germany, the root was little used. It was in fact subsequently nearly forgotten until revived by the introduction of certain secret remedies for tapeworm, of which powdered male fern rhizome, combined with drastic purgatives, was a chief constituent.

[2727] Especially _L. annotinum_, _L. complanatum_ and _L. inundatum_.

[2728] Murray, _Apparatus medicaminum_, v. (1790) 453-471.

[2729] Lib. 4, cap. 156 of the work quoted in the Appendix.

[2730] _Medicin-chymische Apotheke_, Nürnberg, 1656. 20.

[2731] P. 547 of the work quoted in the Appendix.

A medicine of this kind was prepared by Daniel Mathieu, a native of Neuchâtel, born in 1741, who established himself as an apothecary in Berlin. His treatment for the parasite was so successful that it attracted the notice of Frederick the Great, who purchased his nostrum for an annuity of 200 _thalers_ (£30), besides conferring upon him the dignity of Aulic Councillor.[2732]

Great celebrity was also gained for the method of treating tapeworm practised by Madame Nuffler or Nuffer, the widow of a surgeon at Murten (Morat), likewise in Switzerland, who in 1775 obtained for the secret from Louis XIV., after an inquiry by _savans_ of the period, the sum of 18,000 livres. Her method of treatment consisted in the administration of—1. Panada made of bread with a little butter. 2. A clyster of salt water and olive oil. 3. The “_spécifique_”—simply _powdered fern root_. 4. A purgative bolus of calomel, gamboge, acammony, and _Confectio hyacinthidis_,—given in the foregoing order.[2733]

J. Peschier,[2734] a pharmacien of Geneva, recommended as a substitute for the bulky powder of the root, an ethereal extract, an efficient preparation, which though proposed in 1825, was scarcely used in England until about 1851; at present it is the only form in which male fern is employed. Peschier already observed a crystallized deposit in his extract.

=Description=—The fresh rhizome or caudex is short and massive, 2-3 inches in diameter, decumbent, or rising a few inches above the ground, and bearing on its summit a circular tuft of fronds, which in their lower part are thickly beset with brown chaffy scales. Below the growing fronds are the remains of those of previous seasons, which retain in their firm, fleshy bases, vitality and succulence for years after their upper portion has perished. From among these fleshy bases, spring the black, wiry, branching roots.[2735] The rhizome is rather fleshy, and easily cut with a knife, internally of a bright pale yellowish green; it has very little odour and a sweetish astringent taste. For pharmaceutical use, it should be collected in the late autumn, winter or early spring, divested of the dead portions, split open, dried with a gentle heat, reduced to coarse powder, and at once exhausted with ether. Extract obtained in this way is more efficient than that which has been got from rhizome that has been kept some time.

[2732] Cornaz, _Les familles médicales de la ville de Neuchâtel_, 1864. 20.

[2733] _Traitement contre le Ténia ou ver solitaire, pratiqué à Morat en Suisse, examiné et éprouvé à Paris._ Publié par ordre du Roi, 1775. 4°, pp. 30. 3 plates, one representing the plant, its rhizome and leaves.—Also English translation by Dr. Simmons, London, 1778. 8°.

[2734] _Bibliothèque Universelle_, xxx. (1825) 205; xxx. (1826) 326.

[2735] For a full account of the growth and structure of that rhizome see Luerssen, _Medicinisch-pharmaceutische Botanik_, i. (1878) 504. 561.

=Microscopic Structure=—On transverse section of the rootstock, the tissue shows rounded, somewhat polyhedral cells with porous walls; the outer cells are brown and rather smaller, but do not exhibit the regular flattened shape, usual in many suberous coats. Within this cortical layer, there is a circle of about 10 large vascular bundles, besides a large number of smaller ones scattered beyond the circle. The leaf-bases exhibit a somewhat different structure, their vascular bundles, usually 8, forming but one diffuse circle.

The cells of the parenchyme contain starch, greenish or brownish granules of tannic matter, and drops of oil. In the green, vigorously vegetating parts of the rootstock there are numerous smaller and larger intercellular spaces, into which a few stalked glands project, as shown by Prof. Schacht of Bonn in 1863. These globular glands originate from the cells bordering the intercellular spaces. After their complete development, and the appearance of starch in the adjacent parenchyme, they exude a greenish fluid, which when thin slices of the rhizome are kept some time in glycerin, solidifies in acicular crystals.[2736] Such glands appear to be wanting in most of the allied ferns, such as _Aspidium Oreopteris_ Sw. and _Asplenium Filix fœmina_ Bernh. They have been observed by one of us (F.), in the small rhizome of _A. spinulosum_ Sw. Similar glands, but not exuding a green liquid, occur between the paleæ below the vegetating cone of the rootstock.

=Chemical Composition=—Of the numerous examinations which have been made of this drug, those of Bock (1852), of Luck (1860), and of Kruse (1876), may be especially mentioned. Besides the universally distributed constituents of plants, there have been found in the rhizome 5 to 6 per cent. of a green fatty oil, traces of volatile oil, resin, tannin (Luck’s _Tannaspidic_ and _Pteritannic Acids_) and crystallizable sugar, which according to Bock is probably cane sugar.

The medicinal ethereal extract, of which the rhizome yields about 8 per cent., deposits a colourless, granular, crystalline substance, noticed by Peschier as early as 1826, and subsequently designated by Luck, _Filicic Acid_. Grabowski (1867) assigned it the formula C₁₄H₁₈O₅. We learn from Prof. Buchheim that he regards filicic acid as the source of the medicinal efficacy of the drug. By fusion with potash, filicic acid is converted into phloroglucin and butyric acid. The green liquid portion of the extract consists mainly of a glyceride called _Filixolin_, from which Luck obtained by saponification two acids, the one volatile, _Filosmylic Acid_, the other non-volatile, termed _Filixolic Acid_.

Malin (1867) showed that the tannic acid of male fern may be decomposed by boiling dilute acids into sugar and a red substance, _Filix-red_, C₂₆H₁₈O₁₂, analogous to Cinchona-red.

Schoonbroodt[2737] performed some interesting experiments with _fresh_ fern root, showing that it contains _volatile acids_ of the fatty series, among which is probably _formic_; but also a fixed acid, accompanied by an oil of disagreeable odour. The liquid distilled from the dried root did not evolve a similar odour, nor did it contain any acid body. A small quantity of essential oil was obtained by means of ether from the alcoholic extract of the fresh but not of the dried rootstock. The rhizome of male fern yields 2 to 3 per cent. of ash, consisting mainly of phosphates, carbonates, and sulphates of calcium and potassium, together with silica.

[2736] The chemical nature of this body remains to be ascertained. The crystals are probably _Filicic Acid_, accompanied by chlorophyl and essential oil.

[2737] _Journal de Médecine de Bruxelles_, 1867 and 1868—also in the _Jahresbericht_ of Wiggers and Husemann, 1869. 21.

=Uses=—The ethereal extract has been prescribed for all kinds of intestinal worms; but recent experience goes to prove that its effects are chiefly exhibited in cases of tapeworm. It is equally and thoroughly efficacious in the three kinds respectively termed _Tænia solium_, _T. medio-cannellata_ and _Bothriocephalus latus_.

=Substitution=—The rhizomes of _Asplenium Filix fœmina_ Bernh., _Aspidium montanum_ Vogl. (_A. Oreopteris_ Sw.) and _A. spinulosum_ Sw. may scarcely be mistaken for that of _A. Filix mas_. The best means of distinguishing them is afforded by transverse sections of the leaf-bases. In _Filix mas_, the section exhibits 8 vascular bundles,—in the other ferns named, only 2,—a difference easily ascertained by examination under a lens. Practically, no other indigenous fern than _A. Filix mas_ affords a rhizome of sufficient bulk so as to be remunerative. We are not acquainted with that of the American _Aspidium marginale_ Swartz, the section of which shows 6 vascular bundles; its extract is stated by Cressler (1878) to be perfectly active.

=_Thallogens._=

LICHENES.

LICHEN ISLANDICUS.

_Iceland Moss_; F. _Lichen ou Mousse d’Islande_; G. _Isländisches Moos_.

=Botanical Origin=—_Cetraria islandica_ Acharius.[2738]—It is abundant in high northern latitudes, as Greenland, Spitzbergen, Siberia, Scandinavia and Iceland, where it grows even in the plains. It is found in the mountainous parts of Great Britain, France, Italy, and Spain, in Switzerland (in elevations of nearly 10,000 feet), and in the Southern Danubian countries. It also occurs in North America and in the Antarctic regions.

=History=—In the North of Europe, this lichen has long been used under the general name of _Mosi_, _Mossa_ or _Mus_,[2739] as an article of food. It is the _Muscus crispæ Lactucæ similis_ of Valerius Cordus,[2740] and was also mentioned by Ole Borrich, of Copenhagen (1671), who called it _Muscus catharticus_, under the notion that in early spring it possesses purgative properties.[2741] The pharmaceutical tariff of the same city, of the year 1672, likewise quotes _Muscus catharticus islandicus_.[2742] Its medicinal employment in pulmonary disorders was favourably spoken of by Hjärne in 1683,[2743] but it is only since 1757 that it has come into general use as a medicine, chiefly on the recommendation of Linnæus and Scopoli.

=Description=[2744]—The plant consists of an erect, foliaceous, branching thallus, about 4 inches high, curled, channelled or rolled into tubes, terminating in spreading truncate, flattened lobes, the edges of which are fringed with short thick prominences. The thallus is smooth, grey, or of a light olive-brown; the under surface is paler and irregularly beset with depressed white spots. The apothecia (fruits), which are not very common, appear at the apices of the thallus, as rounded boss-like bodies, ²/₁₀ to ³/₁₀ of an inch across, of a dark, rusty colour. The colour and mode of division of the thallus vary greatly, so that many varieties of the plant have been distinguished.

[2738] _Cetraria_ from _cetra_, an ancient shield of hide, in allusion to the circular apothecia.

[2739] These names are generally applied in Scandinavia and Iceland to the smaller cryptogams, as lichens, true mosses, lycopodium, etc.

[2740] Hist. stirpium, quoted in the Appendix.

[2741] Bergius, _Materia Medica_, Stockholm, ii. (1778) 856.

[2742] Flückiger, _Documente_, quoted at page 404.

[2743] Murray, _Apparatus Medicaminum_, v. (1790) 510.

[2744] For an exhaustive account and figures see Luerssen (quoted at p. 734) p. 176.

In the dry state, Iceland moss is light, harsh and springy; it absorbs water in which it is placed to the extent of a third of its weight, becoming soft and cartilaginous; it ordinarily contains about 10 per cent. of hygroscopic water. It is inodorous, but when wetted has a slight seaweed-like smell; its taste is slightly bitter.

=Microscopic Structure=—A transverse section exhibits, when strongly magnified, a broad loose central layer of long, thick-walled branching walls of _hyphæ_, containing air, and enclosing wide hollow spaces. This middle layer encloses a certain number of larger cells called _gonidia_, coloured with chlorophyll. The gonidia are not destroyed either by strong sulphuric acid, or by boiling them with potash. They assume however a deep violet colour when treated with caustic potash and then left for 24 hours in a solution of iodine in potassium iodide.

The tissues on either side of this central layer consists of very thickly felted hyphæ, without intervening spaces, and does not appear to contain any particular substance. This compact and tenacious tissue passes into a thin cortical layer consisting of cells very closely bound together. Under the influence of reagents this layer becomes very evident: thus when moistened with strong sulphuric or hydrochloric acid, it separates from the rest of the tissue as a coherent membrane, and rolls itself backward. On boiling with water the inner tissue swells up, the cell-walls being partly dissolved. Thin slices of the lichen are coloured reddish or pale blue by iodine water,—more distinctly blue, if previously treated with sulphuric acid. The colour spreads uniformly over the inner tissue, but no starch granules can be detected; the cortical layer is merely coloured brown by iodine. The white spots on the outer surface of the thallus are resolved by pressure under a plate of glass into minute round transparent granules, not coloured by iodine, and thick branched cells like those of the central layer.

The short thick prominences on the edge of the thallus, frequently terminate in one or more sac-like cavities (_spermogonia_) containing a large number of simple bar-shaped cells (_spermatia_), only 6 mkm. long; they are enveloped in transparent mucus, and may be expelled by pressure under glass. It has been shown by Stahl (1874) that they represent the fertilizing corpuscles or seaweeds of the class _Florideæ_.

The observations of De Bary (1866) and Schwendener (1867-70) confirmed and much extended by the researches of Bornet[2745] (1873-74), have shown that the gonidia of lichens are referable to some species of _Alga_, and are capable of an independent existence; that the relations of the hyphæ to the gonidia are of such a nature as to exclude the possibility of either of those bodies being produced by the other; and further that the theory of parasitism is the only one capable of explaining these relations in a satisfactory manner. Under this singular theory, lichens are compound organisms, formed of an alga, and of a fungus living upon it as a parasite.

[2745] _Recherches sur les gonidies des Lichens._—_Ann. des Sciences nat._ Bot. xvii. (1873) 45-110; 11 plates; also xix. (1874) 314-320.—For a complete abstract of these and all the more recent investigations on this subject, see Luerssen (_l.c._) 186 _et seq._

=Chemical Composition=—Boiling water extracts from Iceland moss as much as 70 per cent. of the so-called _Lichenin_, or _Lichen-starch_, a body which is perfectly devoid of structure. The decoction (1: 20) gelatinizes on cooling, and assumes a reddish or bluish tint by solution of iodine. This property of lichenin is plainly seen, when the drug is first exhausted by boiling spirit of wine containing some carbonate of potassium; and then boiled with 50 to 100 parts of water, and the decoction precipitated by means of alcohol. The lichenin thus obtained in a purer state, must be deprived of alcohol by cautiously washing it with water. Powdered iodine will now immediately impart to it while still moist an _intense blue_. Its composition, C₁₂H₂₀O₁₀, agrees with that of starch and cellulose; and it must be regarded as a modification of the latter, being likewise soluble in water and in ammoniacal solution of copper. Lichenin is not a kind of mucilage, because it yields but insignificant traces of mucic acid, if treated with concentrated nitric acid; and also because it contains no inorganic constituents.[2746] The very trifling proportion of mucic acid it furnishes may depend upon the presence, in small amount, of an independent mucilaginous body.

According to Th. Berg (1873), lichenin consists of what he continues to call so, and another constituent, the latter only being coloured by iodine, possessing (dextrogyre) rotatory power, and also being insoluble in ammoniacal solution of copper. Berg’s lichenin is not soluble in cold water, but readily dissolves in hot water, and again separates on cooling. The other constituent on the contrary is abundantly soluble in cold, and very sparingly in hot water. The drug yielded to Berg 20 per cent. of “true” lichenin and 10 per cent. of the other substance.

The chlorophyll of the gonidia is not soluble in hydrochloric acid, and hence is distinguished by Knop and Schnedermann as _Thallochlor_; its quantity is extremely small.

The bitter principle of Cetraria, called _Cetraric Acid_ or _Cetrarin_, C₁₈H₁₆O₈, crystallizes in microscopic needles, is nearly insoluble in cold water, and forms with alkalis, yellow, easily soluble, bitter salts. The lichen also contains a little sugar, and about 1 per cent. of a peculiar body, _Licheno-stearic Acid_, C₁₄H₃₄O₃, the crystals of which melt at 120° C. The _Lichenic Acid_ found by Pfaff in 1826 in Iceland moss, and formerly regarded as a peculiar compound, has been proved identical with fumaric acid.

In common with many lichens, cetraria contains _Oxalic Acid_ and is said to yield also some tartaric acid. The ash, which amounts to 1-2 per cent., consists to the extent of two-fifths of silicic acid combined chiefly with potash and lime.

=Collection and Commerce=—Iceland moss is collected in many districts where the plant abounds at least for local use, as in Sweden, whence some is shipped to other countries. It is also gathered in Switzerland, especially on the mountains of the Canton of Lucerne, and in Spain.[2747] None is exported from Iceland.

[2746] The various mucilages and gums yield from 4 to 20 per cent. of ash, but lichenin yields _none_.

[2747] _Cat. of Spanish Productions_,—London Exhibition, 1851.

=Uses=—It is given in decoction as a mild tonic, combined with more

## active medicines. It is very little employed in Iceland, and only

in seasons of scarcity, when it is sometimes ground and mixed with the flour used in making the _grout_ or grain soup. Occasionally it is taken boiled in milk. It is not given, as has been asserted, to domestic animals.

An interesting application of Iceland moss has recently been tried in Sweden. Sten-Stenberg treats it with sulphuric or hydrochloric acid, when 72 per cent. of grape sugar are formed, which may be converted into alcohol.[2748]

FUNGI.

SECALE CORNUTUM.

_Ergota_; _Ergot of Rye_,[2749] _Spurred Rye_; F. _Seigle ergoté_; G. _Mutterkorn_.

=Botanical Origin=—_Claviceps purpurea_ Tulasne, a fungus of the order _Pyrenomycetes_, of which ergot is an immature form, it being the _sclerotium_ (termed in the British Pharmacopœia _compact mycelium_ or _spawn_) developed within the paleæ of numerous plants of the order _Gramineæ_.

Ergot is obtained almost exclusively from rye, _Secale cereale_ L.; but the same fungus is produced on grasses belonging to many other genera, as _Agropyrum_, _Alopecurus_, _Ammophila_, _Anthoxanthum_, _Arrhenatherum_, _Avena_, _Brachypodium_, _Calamagrostis_, _Dactylis_, _Glyceria_, _Hordeum_, _Lolium_, _Poa_, and _Triticum_. Other organisms of diverse form, but of doubtful specific distinctness, are developed in _Molinia_, _Oryza_, _Phragmites_, and other grasses. In the order _Cyperaceæ_ (e.g., _Scirpus_), peculiar ergots are known.

=History=—Although it is hardly possible that so singular a production as ergot should be unnoticed in the writings of the classical authors, we believe no undoubted reference to it has been discovered.[2750] The earliest date under which we find ergot mentioned on account of its obstetric virtues is towards the middle of the 16th century, by Adam Lonicer of Frankfort, who describes its appearance in the ears of rye, and adds that it is regarded by women to be of remarkable and certain efficacy.[2751] It is also very clearly described in the writings of Johannes Thalius, who speaks of it as used “_ad sistendum sanguinem_.”[2752] In the next century it was noticed by Caspar Bauhin, who termed it _Secale luxurians_,[2753] and by the English botanist Ray,[2754] with allusion to its medicinal properties.

Rathlaw, a Dutch accoucheur, employed ergot in 1747. Thirty years later Desgranges of Lyons prescribed it with success; but its peculiar and important properties were hardly allowed until the commencement of the present century, when Dr. Stearns of New York succeeded in gaining for them fuller recognition.[2755] Ergot of rye was not, however, admitted into the London Pharmacopœia until 1836.[2756]

[2748] Dingler’s _Polytechnisches Journal_, 197 (1870) 177; also _Chemisches Centralblatt_, 1870. 607.

[2749] From the French _ergot_, anciently _argot_, a cock’s spur.

[2750] Consult Pliny’s _Nat. Hist._