CHAPTER XIII
SAURIA, _continued_–OPHIDIA–SNAKES
ORDER II. OPHIDIA–_SNAKES_.
_Saurians which have the right and left halves of the lower jaw connected by an elastic band._
The Snakes are the most highly specialised branch of the Sauria, from which they do not differ in any fundamental characters. The chief modifications consist in the absence of the limbs and limb-girdles (a feature intimately correlated with the much-elongated body), and in the swallowing apparatus. The reduction of the limbs and the elongation of the body also occurs in many Lacertilia; in several of the older families of Snakes (_e.g._ Typhlopidae and Boidae) vestiges of the hind-limbs and even of the pelvis are still in existence. Even the peculiar suspensorial apparatus of the lower jaw approaches that of the Lacertilia in the burrowing Ilysiidae and in _Xenopeltis_.
In the majority of the Snakes the quadrate is very loosely suspended from the squamosal (by some authorities homologised with the supratemporal bone of other reptiles), and this again is loosely attached to the lateral parietal region of the skull, placed horizontally, and elongated so far backwards that the vertically placed quadrate lies in a plane behind the skull. In most Snakes the elongated pterygoids are loosely attached to the inner side of the distal end of the quadrates, and they also often touch the mandibles. The whole palatal apparatus is movably attached to the skull, except in some burrowing families. The right and left pterygoids and palatines are widely separated from each other. The pterygoids and maxillaries, connected by the ectopterygoids, are absent, owing to reduction, in the {582}Typhlopidae and Glauconiidae only. The premaxilla is unpaired and small, and is rarely furnished with teeth. The latter are always sharp and recurved, and are lodged in sockets upon the edge of the supporting bone, with which they become firmly ankylosed. There is a perpetual succession of teeth. In the majority of Snakes teeth are carried by the maxillaries, palatines, pterygoids, and dentaries, rarely by the premaxillaries. The palatal teeth are restricted to the palatines in _Oligodon_, _Dasypeltis_, and _Atractaspis_ only.
Peculiar modifications prevail in the poisonous Snakes. Those maxillary teeth which are at their base in connexion with the openings of poison-glands (modified upper labial glands), either have a furrow on the anterior side (Proteroglypha if the anterior teeth are grooved, _e.g._ the Cobras; Opisthoglypha if some of the posterior teeth are grooved), or the groove is converted into a canal, as in the Solenoglypha or Viperidae. The special modification of the maxillaries of the vipers with their long poison-fangs is described on pp. 587 and 637.
The orbit is generally closed behind by the postfrontal. Quadrato-jugal, postfronto-squamosal, and other arches are absent, so that the temporal fossa is quite open (see Fig. 156, p. 597, and Fig. 155, p. 596). The occipital condyle is distinctly triple. The mandibles are composed of several bones, but the coronoid is absent in the Xenopeltidae, Colubridae, Amblycephalidae, and Viperidae; it is large in the Boidae, reduced to a nodule in the Ilysiidae.
The parietals are always fused into a large unpaired bone, which generally forms a sharp crest and partly overlaps the occipitals; there is no interparietal or pineal foramen.
The vertebral column consists of many, often nearly three hundred vertebrae, and these skeletal segments correspond in number with those of the ventral and transverse scales of the skin. The vertebrae are procoelous; in addition to the anterior and posterior zygapophyses they have a pair of accessory articulations on the neural arches, dorsally to the zygapophyses;–the "zygantrum" carried by the posterior end of the neural arches, its articular surfaces looking upwards; and the "zygosphene" carried by the anterior end and looking downwards. Such accessory articulations occur also in a few Lizards, _e.g._ Iguanidae. The vertebrae of many Snakes have unpaired vertical, blade-like {583}haemapophyses on their centra for the more effective attachment of the muscles. All the vertebrae, except the atlas, carry ribs. These articulate by their capitular portions only, and are very movable in a head- and tail-ward direction. The ribs being long, and fitting with their ventral ends into the connective tissue of the sides of the ventral transverse scales, are the principal agents in pushing the body forwards, the posterior edges of these scales being sharp and imbricating.
The skin is covered with scales, absolutely devoid of osteoderms. When the scales are enlarged they are called shields. The keel, a common feature, is caused by a slight ridge of the cutaneous part of the scale. The whole skin is covered with a thin layer of horny epidermis, which is shed frequently, at least several times in one year; the shedding begins at the lips, and the whole outer skin is turned inside out from head to tail, retaining every minute detail of the cutaneous scales; even the watch-glass-like covering of the eyes is preserved.
The eyes are peculiar in so far as they possess no lids. The latter are still present in a vestigial condition in the embryo, but their place is taken by what is probably a modification of the nictitating membrane, which is drawn over the eye and covered with a single transparent scale of the horny skin, like a watch-glass. The eyes themselves are quite movable. The "tears," which of course cannot appear on the outside, are drained off into the nasal cavities by the naso-lacrymal ducts.
The ear is likewise peculiar. There is a long columellar rod with a fibrous or cartilaginous pad at the outer end, which plays against the middle of the shaft of the quadrate, an arrangement which, we must assume, produces a thundering noise in the internal ear, since every motion of the quadrate during the act of swallowing conveys the vibrations directly to the fenestra ovalis. The tympanic cavity, the Eustachian tubes, and the tympanum are abolished, and no external traces of the ear are visible. However, in spite of all this, Snakes can hear very well.
The nose is well developed, and many Snakes, for instance the Grass-Snake, are guided to their prey as much by the sense of smell as by the eyes and ears. The tongue is slender, very protractile and bifid, always moist, and furnished with many sensory corpuscles. It acts entirely as an additional sense-organ, hence the incessant play of the tongue of a snake which wants {584}to investigate anything. In spite of the protractility of the tongue, the hyoid apparatus is very small; the hyoid arches themselves are reduced to mere vestiges near the base of the first and only branchial arches, which are thread-like and extend backwards down the throat.
The trachea is very long, and opens far forwards in the mouth; it can be slightly protruded between the two halves of the lower jaw so as not to be blocked during the act of swallowing. This is a laborious process. The snake, having got hold of its prey with its teeth, generally shifts it into the most convenient position, in order to swallow the head first. One half of the mandible is then pushed forwards, then the other half; the recurved teeth afford the necessary hold, and the snake, little by little, draws its mouth-cavity, and later on itself, over the prey. In fact, it literally gets outside it. Sometimes with a large victim this process may last for hours; the whole mouth and head become painfully distended and the veins swollen almost to bursting. The snake pushes the prey against a stone or other obstacle, rests awhile quite exhausted, and begins afresh. At last the bulk of the prey has passed the mouth, the skin of the neck is stretched to the utmost, the scales being separated by wide interstices, the ribs work spasmodically, the victim is pressed into the shape of a sausage, and the deed is done. In order to assist deglutition there is a great amount of salivation, but the often-heard story that Snakes cover their prey with saliva before they swallow it, is a fable, or based upon faulty observation, snakes sometimes being forced to disgorge the half-swallowed prey, which, in such a case, is covered with slime. One of my tame snakes had swallowed a frog on my table when a friend entered the room. The snake was frightened, jumped on to the ground, striking it with its full belly, and thereby hurting the frog, which squeaked loudly, whereupon the snake reversed its mechanism and the frog hopped away, none the worse for its terrible experience.
In correlation with the elongated narrow space of the body-cavity the lungs are not equally developed, the right being much smaller than the left. The latter is a very thin-walled, hollow bag, and the posterior half or third scarcely contains any of the honey-comb-like respiratory "cells," but acts merely as a reservoir of air.
{585}The cloacal arrangement is essentially the same as that of the Lacertilia, but Snakes possess no urinary bladder. The copulatory organs are stowed away beneath the skin in recesses of the posterior lateral corners of the shallow cloacal vestibulum. Each organ is generally bifurcated at the free end, and furnished with little spike-shaped, but scarcely horny, excrescences. On each side of the outer cloacal chamber, in both sexes, lies a roundish gland with an offensive, strongly-scented secretion; that of various Boas smells disagreeably sweet and musky. The majority of Snakes lay eggs, but most of the Viperidae and the thoroughly aquatic kinds, besides a few terrestrial forms, are viviparous. The egg-shells are like parchment, with very little or no calcareous deposit, so that they are always soft; many embryos are, however, provided with a little "egg-tooth" on the tip of the snout.
[Illustration: FIG. 153.–Map showing the distribution of dangerously poisonous snakes.]
Snakes are intelligent creatures; some become quite affectionate in captivity, but most of them are of a morose disposition, and do not care for company.
The GEOGRAPHICAL DISTRIBUTION of Snakes has been dealt with in detail in connexion with the various families. Unfortunately very few fossils are known. One of the oldest is _Palaeophis_, of the London clay (Lower Eocene). Remains of Elapine and of innocuous Colubrine snakes have been found in the Lower Miocene of Germany; Crotaline forms are known from the Miocene of Turkey and North America. All the Plistocene {586}remains belong to recent genera. There are indications that the Ophidia are a relatively young branch of Reptilia, essentially of Tertiary date, but the foundations of the distribution of most of the older families were laid in Miocene times. The older families, notably those which still possess vestiges of hind-limbs or of the pelvis, are circumtropical, _e.g._ Typhlopidae, Boidae. The few survivors of the Glauconiidae are likewise circumtropical, with the exception of Australia. The Ilysiidae occur in South-Eastern Asia and in tropical South America; their offshoot the Uropeltidae are restricted to India and Ceylon. The Colubridae and even many of their sub-families are cosmopolitan. It is quite possible that the Opisthoglypha and Proteroglypha are not natural groups, but that their respective conditions have been developed on various occasions and in different countries. The same applies more strongly to the Viperidae, a further development of the Opisthoglyphous type. To judge from their distribution, the Crotaline snakes were possibly developed in the Palaearctic sub-region; they spread all over America, but they were debarred from entering either Australia or Africa. The Viperidae, on the other hand, are restricted entirely to the Palaeotropical region and to the Palaearctic sub-region. The fact that no separating belt of water existed for them between Europe and Africa, indicates their being the most recently developed of poisonous snakes. Madagascar is the only large country which, besides snakeless New Zealand, enjoys a total absence of poisonous snakes of any kind, while the Oriental is the only sub-region which suffers from the presence of numerous species of every sub-family of poisonous Elapine, Crotaline, and Viperine snakes.
_Snake-Poison._–Many Snakes, belonging to different families, are poisonous, and unfortunately there is no external character, easily ascertained, by which every poisonous snake can be distinguished from a harmless kind. If the head is very broad, this is probably due to the pair of poison-glands on the sides of the head; but many harmless snakes can flatten and broaden their heads in a suspicious way, and, what is much worse, many of the most poisonous snakes, for instance the Cobras, have a head as smooth and as sleek-looking as the Grass- or Ring-Snake, the most harmless of species. It so happens that, with a few exceptions, for instance among the Crotalines and Vipers, no {587}badly poisonous snake has loreal shields, _i.e._ a pair of shields intercalated between the nasals and the preoculars, but this character is obviously no good for any practical purposes. Therefore, unless you know a snake well enough when you see it, leave it alone, because a mistake may be fatal.
The poison is secreted in modified upper labial glands, or in a pair of large glands which are the homologues of the parotid salivary glands of other animals.[174] A duct passes from the gland forwards along the side of the upper jaw. Just in front of the fang it doubles on itself, so as to open by a small papilla on the anterior wall of the sheath of mucous membrane which embraces the base of the tooth like a pocket. As mentioned before (p. 582), the poison is conveyed either along a furrow on the anterior side of the tooth, or the growing substance of the tooth partly converts the furrow into a canal which opens only near the end of the tooth. This is a perfectly devilish contrivance, ensuring the conveyance of the poison into the very deepest part of the wound. The Elapinae have relatively short fangs, while those of the Vipers, and especially those of the Crotaline snakes, are much longer, sometimes measuring nearly an inch in length. The most formidable apparatus is that of the Viperidae, since in them the maxillaries, each provided with only one acting fang, and without any other teeth behind, can be erected. The mechanism is explained in Fig. 154 and Fig. 179 (p. 647). The apparatus of the upper jaw is so constructed that the pushing forwards of the horizontal pterygoid bar will, by acting on the ectopterygoid, rotate and erect the short maxillary. The pulling forwards is effected by contraction of the spheno-pterygoid muscle, which arises far forwards from the basal orbito-sphenoid region, and is inserted on to the inner dorsal surface of the pterygoid. The principal closing muscles of the mouth are the temporo-masseteric muscles (Fig. 179, _T.a._ and _T.p._) and the inner and outer pterygoid muscles, which latter arise from the outer surface of the pterygoid bone, or from the maxillary, and are inserted on to the articular region of the mandible.
A strong ligament arises from the squamoso-quadrate junction, and spreads fan-shaped upon the connective tissue {588}wall of the poison-gland; the anterior and posterior ends of the gland are held by another strong band, which stretches from the maxilla to the mandibular joint. The whole is so arranged that the acts of opening the jaws (by the digastric muscles) and the erection of the fang-bearing maxillaries are enough to mechanically squeeze the contents out of the poison-gland. A portion of the anterior temporal muscle is attached to the capsule of the poison-gland.
[Illustration: FIG. 154.–Explanation of the biting mechanism of a rattlesnake. _Ia_ and _Ib_, position of the apparatus when the mouth is shut. _IIa_ and _IIb_, position of the apparatus when the mouth is opened widely; the spheno-pterygoid muscle (_P.e_) is contracted, the pterygoid (_Pt_) is pulled forwards, the transverse bone or ectopterygoid (_Tr_) pushes the maxillary (_M_), rotates it and thereby causes the poison-fang (_J_) to assume an erect position. _Di_, Digastric muscle, contraction of which lowers, or opens, the lower jaw; _G_, the groove or pit characteristic of the Crotaline snakes; _J_, poison-fang; _M_, maxillary; _P_, palatine; _P.e_, spheno-pterygoid muscle; _Pm_, premaxillary; _Pt_, pterygoid; _Q_, quadrate; _Sq_, squamosal; _T.a_, insertion of the anterior temporal muscle, by contraction of which the mouth is shut; cf. Fig. 179 (p. 647); _Tr_, transversum or ectopterygoid; X, origin and insertion of a muscle and a strong ligament, contraction of which draws the maxillary and its tooth back into the position of rest and assists in shutting the mouth.]
An excellent account of the nature and of the effect of the venom of Snakes has been written by Charles J. Martin.[175] The following condensed account has been abstracted from it:–
"The poison is a clear, pale yellow, or straw-coloured fluid, {589}which reacts acid, and contains about 30 per cent of solids, but this varies much according to the state of concentration. Most venoms are tasteless, but Cobra poison is said to be disagreeably bitter. Dried venom keeps indefinitely, and dissolves readily in water. It keeps also in glycerine. It contains albuminous bodies in solution. The venom is, in fact, a pure solution of two or more poisonous proteids, which are the active agents, with a small quantity of an organic acid or colouring matter. The venom is destroyed by reagents which precipitate proteids in an insoluble form, or which destroy them, _e.g._ silver nitrate or permanganate of potash. Hypochlorites have the same effect. Carbolic acid and caustic potash destroy it only after a day or two.
"The venom is generally introduced into the subcutaneous tissue, whence it reaches the general circulation by absorption through the lymph and blood-vessels. When introduced directly into a vein, the effects are instantaneous. It is absorbed by the conjunctiva, but, excepting Cobra poison, not by the mouth or alimentary canal, provided there be no hollow teeth or no abrasions. The venom of the various kinds of Snakes acts differently.
"The symptoms of Cobra poison. Burning pain, followed by sleepiness, and weakness in the legs after half an hour. Then profuse salivation, paralysis of the tongue and larynx, and inability to speak. Vomiting. Incapability of movement. The patient seems to be conscious, but is unable to express himself. The breathing becomes difficult. The heart's action is quickened. The pupil remains contracted and reacts to light. At length breathing ceases, with or without convulsions, and the heart slowly stops. Should the patient survive, he returns rapidly to complete health.
"The symptoms of Rattle-snake poison. The painful wound is speedily discoloured and swollen. Constitutional symptoms appear as a rule in less than fifteen minutes: prostration, staggering, cold sweats, vomiting, feeble and quick pulse, dilatation of the pupil, and slight mental disturbance. In this state the patient may die in about twelve hours. If he recovers from the depression, the local symptoms begin to play a much more important part than in Cobra poisoning: great swelling and discoloration extending up the limb and trunk, rise of {590}temperature and repeated syncope, and laboured respiration. Death may occur in this stage. The local haemorrhagic extravasation frequently suppurates, or becomes gangrenous, and from this the patient may die even weeks afterwards. Recovery is sudden, and within a few hours the patient becomes bright and intelligent.
"Symptoms of bite from the European Viper. Local burning pain; the bitten limb soon swells and is discoloured. Great prostration, vomiting, and cold, clammy perspiration follow within one to three hours. The pulse is very feeble, with slight difficulty in breathing, and restlessness. In severe cases the pulse may become imperceptible, the extremities may become cold, and the patient may pass into coma. In from twelve to twenty-four hours these severe constitutional symptoms usually pass off, but in the meantime the swelling and discoloration have spread enormously. Within a few days recovery usually occurs somewhat suddenly, but death may occur from the severe depression, or from the secondary effects of suppuration.
"Symptoms of bite from the Daboia or _Vipera russelli_. These resemble the effects of Rattle-snake poison, but sanious discharges from the rectum, etc., are an additional and prominent feature. The recovering patient suffers from haemorrhagic extravasations in various organs, besides from the lungs, nose, mouth, and bowels. Kidney haemorrhage and albuminuria is a constant symptom. The pupil is always dilated and insensitive to light.
"Symptoms of bite of Australian Elapine snakes. Pain and local swelling. The first constitutional symptoms appear in fifteen minutes to two hours. First faintness, and an irresistible desire to sleep. Then alarming prostration and vomiting. The pulse is extremely feeble and thread-like, and uncountable. The limbs are cold, and the skin is blanched. Respiration becomes shallow with the increasing coma. Sensation is blunted. The pupil is widely dilated, and insensible to light. There is sometimes passing of blood. If the patient survives the coma, recovery is complete and as a rule rapid, without secondary symptoms. The Australian venom and that of all viperine snakes, perhaps also that of the Cobra, if introduced rapidly into the circulation, occasions extensive intravascular clotting. If the venom is slowly absorbed, the blood loses its coagulability, {591}owing to the breaking down of the red blood-corpuscles, most so with vipers, less with Australian snakes, least so with the Cobra. The Cobra venom is supposed to extinguish the functions of the various nerve-centres of the cerebro-spinal system, the paralysation extending from below upwards, and it has a special affinity for the respiratory centre. The toxicity or relative strength of the Cobra venom has been calculated to be sixteen times that of the European Viper. Snakes can poison each other, even those of the same kind.
"_Treatment._–Apply a ligature above, not on the top of the situation of the bite; twist the string tightly with a stick. Then make a free incision into the wound. Sucking out is dangerous! Then bandage the limb downwards, progressing towards the wound; repeat this several times. Direct application into the widened wound of calcium hypochlorite, i.e. bleaching powder, is very good, or of a 1 per cent solution of permanganate of potash, or Condy's fluid. Amputation of the finger is the best remedy of all if a large snake has bitten it. Do not keep the ligature longer than half an hour. Then let the circulation return, and apply the ligature again. In any case, do not keep the ligature on for more than one hour for fear of gangrene.
"_Internal remedies._–The administration of enormous doses of alcohol is to be condemned strongly; small stimulating doses are good, but stimulation can be more effectively produced by ammonia or strychnia. Hypodermic injection of strychnine, in some cases as much as one to two grains (but not into a vein!) has in some cases had good results; but injection of ammonia, instead of doing any good, has disastrous sloughing results. There is only one fairly reliable treatment, that by serum therapeutics, the injection of considerable quantities of serum of animals which have been
## partially immunised by repeated doses of snake-venom. Unfortunately this
treatment will not often be available."
Several well-known Mammals and Birds are immune by nature against snake-venom, but most of them avoid being bitten. Some birds induce the snake to strike and bite frequently into their spread-out wings. Such more or less immune creatures are the Mongoose, the Hedgehog, and the Pig, the Secretary bird, the Honey Buzzard, the Stork and probably other snake-eaters.
{592}CLASSIFICATION OF OPHIDIA.–Duméril and Bibron[176] divided Snakes according to their teeth into Opotérodonts, Aglyphodonts, Solenoglypha, Proteroglypha, and Opisthoglypha.
J. E. Gray[177] divided Snakes into two sub-orders: Viperina and Colubrinia. Günther[178] distinguished between Ophidii colubriformes, O. colubriformes venenosi (Elapidae and Hydrophidae) and O. viperiformes. Cope[179] laid stress upon the modifications of the squamosal, ectopterygoid, and ectopterygoid bones, and also upon the condition of the vestigial limbs. He divided the snakes into Scolecophidia (Typhlopidae), Catodonta, Tortricina, Asinea (the harmless snakes without limb-vestiges), Proteroglypha, and Solenoglypha.
Boulenger[180] has accepted Cope's principles, and, mainly by combining the Asinea with the Proteroglypha as Colubridae, has produced a logically conceived system, by far the best hitherto proposed. It has been followed in the present work. Boulenger's phylogenetic system stands as follows:–
9 Viperidae 5 Uropeltidae | 8 Amblycephalidae | 7_a_ C. Opisthoglypha 7_b_ C. Proteroglypha | | | | | | +––––––––––––––––––––+––––––––––––+ | | 4 Ilysiidae 7 Colubridae Aglypha | 6 Xenopeltidae | | | | +––––––––––––––––––+–––––––––-–––––––––––––+ | 1 Typhlopidae 3 Boidae 2 Glauconiidae
I. No ectopterygoid; pterygoid not extending to quadrate or to mandible; no supratemporal (squamosal); prefrontal forming a suture with nasal; coronoid present; vestiges of pelvis.
Maxillary vertical, loosely attached, toothed; mandible edentulous; a single pelvic bone. .......... _Typhlopidae_, p. 593.
Maxillary bordering mouth, forming a suture with premaxillary, prefrontal, and frontal, toothless; lower jaw toothed; pubis and ischium present, latter forming a symphysis. .......... _Glauconiidae_, p. 594.
II. Ectopterygoid present; both jaws toothed.
A. Coronoid present; prefrontal in contact with nasal.
1. Vestiges of hind-limbs; supratemporal (squamosal) present.
Squamosal large, suspending quadrate. .......... _Boidae_, p. 596.
Squamosal small, intercalated in the cranial wall. .......... _Ilysiidae_, p. 594.
2. No vestiges of limbs; squamosal absent. .......... _Uropeltidae_, p. 595.
{593}B. Coronoid absent; squamosal present.
1. Maxillary horizontal; pterygoid reaching quadrate or mandible.
Prefrontal bone in contact with nasal. .......... _Xenopeltidae_, p. 605.
Prefrontal not in contact with nasal. .......... _Colubridae_, p. 606.
2. Maxillary horizontal; pterygoid not reaching quadrate or mandible. .......... _Amblycephalidae_, p. 637.
3. Maxillary vertically erectile, perpendicularly to ectopterygoid; pterygoid reaching quadrate or mandible. .......... _Viperidae_, p. 637.
For ordinary practical purposes this synopsis is useless, being based entirely upon anatomical characters, not all easily ascertained. The following characterisation of families may therefore be preferred:–
Eyes vestigial; no teeth in the lower jaw; without enlarged ventral scales. .......... _Typhlopidae._
Eyes vestigial; teeth restricted to the lower jaw; without enlarged ventral scales. .......... _Glauconiidae._
Eyes very small; head not distinct; ventral scales scarcely enlarged; tail extremely short, ending obtusely and covered with peculiar scales. .......... _Uropeltidae._
With vestiges of the hind-limbs appearing as claw-like spurs on each side of the vent; ventral scales transversely enlarged; eyes functional, free.
Ventral scales scarcely enlarged. .......... _Ilysiidae._
Ventral scales transversely enlarged. .......... _Boidae._
With a pair of poison-fangs in the front part of the mouth, carried by the otherwise toothless, much shortened, and vertically erectile maxillaries; ventral scales transversely enlarged; eyes free. .......... _Viperidae._
All the remaining Snakes combine the following characters: the maxillaries are typical, not separately movable, horizontal, with a series of teeth.[181] The mandible is toothed but has no coronoid bone. There are no vestiges of limbs or of their girdles. The eyes are free.
Dentary movably attached to the tip of the articular bone of the mandible; skin beautifully iridescent. .......... _Xenopeltidae._
Without a mental groove; the ends of the pterygoids are free, not reaching the quadrates. .......... _Amblycephalidae._
With a median longitudinal groove between the shields of the chin; the squamosal is horizontally elongated, movable; the pterygoid reaches the quadrate. .......... _Colubridae._
FAM. 1. TYPHLOPIDAE.–Burrowing snakes which have the whole body covered with uniform cycloid scales, and with the teeth restricted to the small and transversely placed maxillary bones. The pterygoids do not extend backwards to the quadrates, and there are no endopterygoids. The quadrates slant obliquely forwards, and are attached directly to the pro-otics, {594}owing to the absence of squamosal bones. The prefrontals are in lateral contact with the nasals. There are vestiges of the pelvis, reduced to a single bone on each side. The eyes are hidden by shields of the skin.
The Typhlopidae, mainly composed of the genus _Typhlops_, with about one hundred species, are undoubtedly the last living descendants of formerly cosmopolitan, rather archaic, snakes, which in adaptation to their burrowing life and insectivorous diet have undergone degradation. They are still widely distributed in all tropical and sub-tropical countries, some on the solitary Christmas Island, but not in New Zealand. One species, _T. vermicularis_, inhabits the Balkan Peninsula and South-West Asia. It is brown above, yellowish below, and reaches a length of about 10 inches. The tail is extremely short and ends in a horny spine. _T. braminus_ is widely distributed in Southern Asia, the Malay Islands, the islands in the Indian Ocean and in Southern Africa.
FAM. 2. GLAUCONIIDAE.–In most respects resembling the Typhlopidae, but the maxillaries retain their normal position and are toothless, teeth being restricted to the lower jaw, which is stout and short. The pelvic girdle and the hind-limbs show the least reduction found in any recent Snakes; in the pelvis the ilia, pubes, and ischia can still be distinguished, the last even retaining their symphysis; there are also vestiges of femurs. About thirty species, nearly all belonging to the genus _Glauconia_, are found in South-Western Asia, Africa, and the warmer parts of America, including the West Indies.
FAM. 3. ILYSIIDAE.–The scales of the cylindrical body are smooth and small, those on the ventral side are scarcely larger. The tail is extremely short and blunt. The head is very small, not distinct from the neck. The gape of the mouth is very narrow. Teeth are carried by the mandibles, the pterygoids, palatines, maxillaries, and one or two or more by the premaxillae. The endopterygoids are short. An important cranial feature is the short quadrates, which stand rather vertically and are connected with the cranium by the squamosals; these are very small and are firmly wedged in between the upper ends of the quadrates and the pro-otic, lateral, and supra-occipital bones; now forming part of the cranial wall. Vestiges of the pelvis and hind-limbs are very incomplete, and terminate in claw-like spurs, {595}protruding between the scales on either side of the vent. The eyes are very small, and are either free or covered by transparent shields. The few, scarcely half-a-dozen, species are found in South America (_Ilysia_) and in Ceylon, the Malay Islands, and Indo-China.
_Ilysia_ (_Tortrix_) _scytale_, the Coral-Snake of Tropical South America, is a beautiful coral-red with black rings. On account of its beauty, perfectly harmless nature, and for "cooling purposes," this snake, which grows to nearly a yard in length, is sometimes worn as a necklace by native ladies. All the Ilysiidae lead a partly burrowing life, live chiefly upon worms, insects, and little Typhlopidae, and are viviparous.
FAM. 4. UROPELTIDAE.–Burrowing snakes of Ceylon and Southern India, with a short and rigid cylindrical body and a very short tail, which ends in a large peculiar shield, often obliquely truncated. The scales of the body are smooth, and are little larger on the belly; the coloration is mostly very beautiful. The eyes are very small.
The Uropeltidae are somewhat intermediate between the Ilysiidae, Glauconiidae, and Boidae. The pterygoids do not reach the quadrates; but ectopterygoids are present; the quadrates are very small and directly attached to the skull, squamosals being absent. Teeth are carried by the mandibles and by the maxillaries, which are normal in their position. There are no vestiges of hind-limbs or of the pelvis. The Uropeltidae, of which about forty species are known, are viviparous, burrow in the ground, and frequent damp localities, preferring mountain-forests. The use of the characteristic tail-shield is not clear; perhaps it assists these rather rigid creatures in digging, by being pressed against the ground.
_Uropeltis._–The tail is obliquely truncated, ending in a roundish, flat shield.
_U. grandis_ s. _philippinus_.–The latter name seems to have misled W. Marshall[182] into including the Philippine Islands in the range of the family, a mistake which is sure to be propagated. The species, the only one of the genus, is confined to Ceylon; it is blackish above, yellow below, frequently with small yellow spots above and brown spots on the under surface. It grows to about 18 inches in length.
{596}_Rhinophis._–The tail-shield is convex and the snout is pointed. _Rh. sanguineus_ of Southern India is black above with a bluish gloss, sometimes with small pale specks; the belly and several of the lateral series of scales are bright red, spotted with black. The tail-shield is black and red.
[Illustration: FIG. 155.–Skull of _Eunectes murinus_. × 1. The teeth on the maxillary, palatine, and pterygoid have been omitted. _Col_, Columella auris; _Cond_, occipital condyle; _E.P._ and _E.Ptg_, ectopterygoid or transverse bone; _F_, frontal; _Mand_, mandible; _Max_, maxillary; _Na_, nasal; _Pal_, palatine; _Par_, parietal; _Pmx_, premaxillary; _Pr.f_, prefrontal; _Pt.f_, postfrontal; _Ptg_, pterygoid; _Q_, quadrate; _Sq_, squamosal; _Tb_, turbinal.]
FAM. 5. BOIDAE.–Typical Snakes, usually large, and with vestiges of pelvis and hind-limbs, appearing externally as claw-like spurs on each side of the vent. The scales of the upper surface are usually small and smooth, while those of the ventral surface form one broad series on the belly, and one or two rows on the tail. The quadrate is carried by the horizontally elongated squamosal, which rests loosely upon the lateral occipital region. The prefrontal is in contact with the nasal. Teeth are carried by the mandibles, the pterygoids, palatines, maxillaries, and, in the Pythoninae, by the premaxillaries also. For further details see Figs. 155, 156.
{597}[Illustration: FIG. 156.–A, Ventral, B, dorsal, view of the skull of _Eunectes murinus_. Lettering as in Fig. 155. × 1.]
The Boidae comprise between sixty and seventy species, which have been grouped into many genera, on unimportant characters, referring to the scales and shields of the head. It is doubtful if they are natural groups, a consideration which detracts much from their value in the study of geographical distribution. Even the two sub-families are not free from this reproach. The range of the family is world-wide, Boidae occurring in all tropical and sub-tropical countries, including islands, except New Zealand. A few species live in South-Eastern Europe (_Eryx_) and in North-Western America. They mostly prefer wooded districts, especially forests; climbing trees, assisted by the short and partly prehensile tail. Others are semi-aquatic, and a few live in sandy localities. They are all rapacious, and by preference feed on warm-blooded creatures, which they constrict by coils of the body in order to hold, kill, and crush the victim before swallowing it. Exaggerated notions are entertained about their swallowing capacity. It is obvious that a large snake, 20 feet long, half a foot thick, and weighing several hundred pounds, can crush a tiger, a stag, or even a {598}cow; but common sense tells us where to draw the line when it comes to the swallowing of the prey. Small game, although of a bulk apparently far too big for the snake, is so crushed and mangled that it is turned into the shape of a sausage preparatory to the long process of swallowing. The Boidae lay eggs, and some species incubate them, or rather the female coils herself round them for the sake of protection. No appreciable amount of extra warmth is developed. Unfortunately the observations of one of the best cases on record[183] were conducted so imperfectly that they are of little value.
SUB-FAM. 1. PYTHONINAE.–With a pair of supra-orbital bones, intercalated between the prefrontal, frontal, and postfrontal bones. The sub-caudal scales are mostly in two rows. The premaxilla often carries a few small teeth.
The Pythoninae, comprising about twenty species, are restricted to the Palaeotropical and Australian regions, with the sole exception of _Loxocemus bicolor_ in Southern Mexico.
_Python_, the principal genus, has teeth on the premaxilla. The rostral, each of the anterior upper labials, and some of the lower labial shields, contain a deep, probably sensory, pit. The maxillary and mandibular teeth are long, but decrease from before backwards. The head is distinct from the neck, and is covered with symmetrical shields or with small scales. The scales of the body are small and smooth. The tail is short and prehensile; below with two rows of scales. The pupil of the eye is vertical. The range of the genus extends over the whole of the Palaeotropical and Australian regions, excepting Madagascar and New Zealand.
_P. spilotes_, the "Carpet Snake" of Australia and New Guinea, is mostly beautifully marked, but is subject to much variation in colour. The more typical specimens are black above, each scale with a yellowish dot, with yellow spots or combinations of dots, more or less arranged in rows. The under parts are yellow. It reaches a length of about two yards, and spends a great part of its time in trees.
_P. reticulatus_ is the commonest species in Indo-China and in the Malay Islands. Four upper labial shields of each side are pitted. The specific name refers to the bold, dark, lozenge-shaped markings upon the lighter yellowish or brown ground. A black {599}line extends over the head from the nose to the neck, and another on each side from the eye to the angle of the mouth. The under parts are mostly yellowish, with small brown spots on the sides.
This is one of the largest species of Python, some specimens being known which measured about 30 feet in length.
[Illustration: FIG. 157.–_Python spilotes_ (the Carpet Snake). × ⅛.]
As a sample of folk-lore connected with this monstrous snake the following Burmese fable has been recorded by Mason:–[184]
"According to a Karen legend all the poisonous serpents derive their virulence from the Python, which, though innocuous now, was originally the only one that was venomous. In those days he was perfectly white, but having seduced away a man's wife, Aunt Eu (Eve), he made her, while she was in his den, weave figures on his skin in the forms which are now seen. At that time, if he bit the footstep of a man in the road, such was the virulence of his poison that the man died, how far soever that man might have passed from the bitten track. The Python had not, however, an ocular demonstration of the fact, so he said to the Crow: 'Crow, go and see whether people die or not when I bite the foot-track.' The Crow went to the neighbourhood of a Karen cabin, and found the people, as is their custom at funerals, laughing, singing, dancing, jumping, and beating drums. He therefore returned to the Python, and told him that so far from {600}his efforts producing death, on the contrary they produced joy. The Python was so angry when he heard this that he ascended a tree and spit up all his venom, but other creeping things came and swallowed it, and people die of their malignancy to this day. The tree, therefore, from which the Python spat up his venom became deadly, and its juice is used to this day for the purpose of poisoning arrows. The Python made the other creatures promise not to bite without provocation. The Cobra said: 'If there be transgression so as to dazzle my eyes, to make my tears fall seven times in one day, I will bite.' So said the Tiger (whose bite the Karens esteem as virulent as a serpent's) and others, and they were allowed to retain their poison. But the Water Snake and Frog said they would bite with or without cause as they liked; so the Python drove them into the water, where their poison melted away and their bite became harmless."
[Illustration: FIG. 158.–_Python molurus._ × ⅒.]
_P. molurus_ is the species of India and Ceylon, ranging, however, also into Indo-China. Boulenger quotes W. Elliot[185] {601}as the authority for the statement that this species grows to the length of 30 feet. Only two pairs of upper labials are pitted. The general colour above is greyish or yellowish brown with a dorsal series of large reddish-brown, black-edged patches, and on the sides of the body with a series of smaller spots with light centres. On the head is a lance-shaped marking; a brown stripe passes from the eye backwards. The under parts are yellowish.
_P. sebae_ and _P. regius_ are African species. The former has two pairs of upper labials pitted, the latter four pairs. _P. sebae_ is generally pale brown above with dark brown, black-edged cross-bars, which are usually connected by a sinuous dark stripe along each side of the back. The upper surface of the tail has a light stripe between two black stripes. The belly is spotted and dotted with dark brown. _P. sebae_ ranges over the whole of Tropical and Southern Africa, perhaps with the exception of Eastern Africa. _P. regius_ of West Africa is beautifully marked, and may be recognised by the dark brown, black-edged band along the back, sending down triangular or Y-shaped processes on the sides, which are pale brown. This dorsal band encloses a light streak on the neck and another on the tail. The belly is yellowish.
These African Pythons grow to a length of about 15 feet, but specimens so large as this are not often met with. The negroes of certain parts of the coast of Guinea are said to worship them and to keep them in special temples, where they are regularly attended to. Their food consists chiefly of small Mammals, notably rats, and of Birds. A couple of these snakes paired in the Zoological Gardens of London in the month of June. The female laid nearly one hundred eggs in the following January, and incubated them until April, when the embryos were found to be still unripe.
SUB-FAM. 2. BOINAE.–Without supra-orbital bones. The premaxilla is toothless. The subcaudal scales form mostly a single row.
The Boinae comprise between forty and fifty species. Most of them are American, but the genus _Eryx_ inhabits North Africa, Greece, and South-Western Asia; the genus _Enygrus_ inhabits New Guinea and many of the Pacific Islands, for instance New Britain (Neu Pommern), the Solomon, Loyalty and Fiji Islands, {602}and the New Hebrides. _Casarea dussumieri_ is found on Round Island near Mauritius; and two species of _Boa_ and one of _Corallus_ represent the Boidae in Madagascar, while all the others live in Central and South America.
_Boa._–The maxillary and mandibular teeth gradually decrease in size. The scales of the upper parts of the body and tail are smooth and very small. The rostral shield is enlarged. The nostrils are placed between two or three nasals, and these are separated from those of the other side by small scales. The tail is short and prehensile. The pupil is vertical.
_B. constrictor_, of South America, has the head covered with small scales, one of the pre-oculars being enlarged. The eye is separated from the labials by several series of tiny scales. The general colour is a delicate "pale brown above, with fifteen to twenty dark brown cross-bars widening on each side, and, if connected by a dark dorso-lateral streak, enclosing large elongate oval spots.... On each side is a series of large dark brown spots with light centres, most of which alternate with the cross-bars. On the tail the markings become much larger, brick-red, edged with black, and separated by narrow, yellowish interspaces." Under parts yellowish with black dots. _Boa constrictor_, a name applied in popular parlance to many species, reaches a length of more than 10 feet; the largest specimen in the British Museum measures exactly 11 feet. A few other species inhabit Central America and the West Indies. _B. dumerili_ and _B. madagascariensis_, both of Madagascar, cannot be separated from the genus _Boa_.
A. D. Bartlett[186] has described the following incident:–
"In the evening of 5th October 1892 two pigeons were put into the cage in which two fine specimens of _Boa constrictor_ had been living on friendly terms since the beginning of the year. The larger snake seized one of the pigeons and the keeper left the house. The next morning only one of the snakes, the larger specimen, was visible, and from its enormously extended body it was evident that it had swallowed its companion, which was about 9 feet in length. It had no longer the power of curling itself round, but remained extended nearly to its full length in a straight line, and appeared to be at least three times its normal circumference. It was almost painful to see the distended skin, {603}which had separated the scales all over the middle of the body. By 2nd November, twenty-eight days later, the snake had not only digested its companion but had regained its appetite as well as its normal size, and it immediately swallowed a pigeon put into its den."
This peculiar case is not one of ordinary cannibalism. It is rather an unintentional accident. When two snakes happen to get hold of the same animal (in the present case a pigeon) and begin to swallow it, the action of swallowing becomes almost mechanical, the snakes continuing to push their jaws over the prey–which in the case of a bird or mammal they cannot taste, nor can they see it–so long as they feel something in the mouth. After the original prey has been mastered, it is the turn of the opposite snake's head, and if the weaker snake does not give way it is swallowed by its stronger mate. Grass-Snakes will swallow several frogs if these are tied together in a string, and other snakes do the same with mice. There are instances on record in which a _Python_ swallowed its blanket, which, being absolutely indigestible, caused its death.
[Illustration: FIG. 159.–Head of _Eunectes murinus_. × 1.]
_Casarea_, the "Round-Island Snake," differs from _Boa_ chiefly by the rough and strongly keeled scales, and by the relatively much longer tail.
_Eunectes murinus_, the "Anaconda," is an aquatic _Boa_. It differs from this genus mainly by the inner of the three nasal shields being in contact with that of the other side (see Fig. 159), and by the absence of the little scales between the eye and the labials; the snout is, moreover, covered with shields instead of small scales. The pupil of the eye is normally vertical, but it had contracted into a round pinhole in the dead but still fresh {604}specimen from which the figure was drawn. The general colour is dark olive-brown, with large oval black spots arranged in two more or less alternating rows along the back, and with smaller black, white-eyed spots along the sides. The under parts are whitish, spotted with black. The upper parts of this and of many other dark-coloured species of Boidae are often shiny, with an iridescent lustre.
The Anaconda combines an arboreal with an aquatic life, a kind of existence eminently in harmony with the well-watered, dense forests of Tropical South America, which are the home of this, the largest of all modern Snakes. It is said to attain a length of as much as 33 feet. There is no inherent impossibility in such statements, but the giant specimens seem to have a knack of keeping out of the naturalist's way.
The Anaconda feeds chiefly upon Birds and Mammals, which it catches either on land, mostly during the night-time, or in the water. For the latter purpose it lies submerged in the rivers or floats about leisurely, only the head being above the surface, and anything suitable is attacked. In other localities the snake, if so inclined, establishes itself upon the branches of a tree which overhangs the water, or the track of the game. These aquatic Snakes seem to be viviparous.
_Eryx_ has the head not distinct from the neck and covered entirely with small scales. Those of the body are likewise small, and are either smooth or keeled. The tail is very short. The anterior maxillary and mandibular teeth are longer than the posterior teeth. These snakes, most of which are less than 3 feet in length, inhabit the sandy districts of North Africa, Arabia, and South-Western Asia, extending into Central Asia. One species, _E. jaculus_, extends into Greece and the Ionian Islands. Like the other species it is an ugly creature, pale grey or yellowish above, with darker patches and spots. The under parts are whitish. The scales are smooth on the front half of the body, becoming keeled further back and on the tail. Total length under 2 feet. The pupil is vertical.
According to Zander[187] and Werner[188] this snake lives in sandy localities, digging itself into the sand, or covering the body lightly with sand and leaving only the eyes and nostrils free. The whole body is very flabby, and presses itself into any irregularity of the {605}ground over which the snake creeps. Some specimens live on lizards, others prefer mice. The prey is caught by the head, and further secured by several turns of the body of the captor, whose tail is then turned forwards, round the head of the victim, so as to form a kind of knot.
Not less striking than their agility is their jealousy, which is so strong that a snake will occasionally leave the mouse which it has just strangled in order to seize another snake's mouse. Sometimes several snakes fight for the same mouse, coiled together into one inextricable lump so that the mouse itself is quite invisible. The snakes poke their heads about in search of the hidden prey, and every attempt of one of the snakes to free itself, causes the others to squeeze it firmer and firmer, thinking apparently that the motion was caused by the lost prey.
Occasionally one of Werner's captives caught several mice in succession. With these it crawled into a corner, dropped the mice, and then proceeded quietly to swallow one after another. After a fortnight the whole repast was digested, and the snake was ready for more.
FAM. 6. XENOPELTIDAE.–The single species, _Xenopeltis unicolor_, of South-Eastern Asia, including the Malay Islands, has been raised to the dignity of family-rank on account of the following combination of characters. The prefrontal bones are still in contact with the nasals as in the previous families, but the coronoid bones of the mandibles are absent as in the remaining families. The whole suspensorial apparatus and the lower jaw itself are peculiar. The dentary bone is movably attached to the end of the much-elongated articular bone, the movability being enhanced by the absence of the coronoid element.[189] The quadrate is short and thick, and is carried by the short and broad squamosal, which lies flat against the skull, resembling in this respect that of some of the Ilysiidae. Boulenger rightly considers _Xenopeltis_ to be in various ways intermediate between this family, the Boidae and the Colubridae. The head is small and not distinct from the neck. The eyes are small and have a vertical pupil. The body is cylindrical, covered above with {606}smooth black or brown and highly iridescent scales, hence the generic name. The ventral scales are white and transversely enlarged as in the majority of snakes. The tail is short, but not stunted, measuring about 4 inches in full-grown specimens of a total length of 3 feet.
FAM. 7. COLUBRIDAE.–This family comprises those snakes (about nine-tenths of all recent species) which combine the following characters:–ectopterygoids are present: the squamosals are loosely attached to the skull, and carry the quadrates, which are not reached by the pterygoids: the prefrontals are not in contact with the nasals: the maxillaries are horizontal and form the greater portion of the upper jaws: the mandibles lack the coronoid process or element: both jaws are toothed.
The best arrangement of this enormous cosmopolitan family with terrestrial, arboreal, and aquatic forms, is that by Boulenger, who, adopting Duméril's terms, has divided them into three parallel series.
A. _Aglypha._–All the teeth are solid and not grooved.
B. _Opisthoglypha._–One or more of the posterior maxillary teeth are grooved.
C. _Proteroglypha._–The anterior maxillary teeth are grooved or "perforated."
The Aglypha are harmless, non-poisonous. Most of the Opisthoglypha are poisonous, although few of them are dangerously so. The Proteroglypha, which comprise the "Cobras" and their allies, are deadly poisonous.
SERIES A. AGLYPHA.
SUB-FAM. 1. ACROCHORDINAE.–The postfrontal bones, besides bordering the orbits posteriorly, are extended forwards so as to form the upper border of the orbits, separating the latter from the frontals. The few genera and species of this sub-family are mostly aquatic, inhabiting rivers, or estuaries with brackish water, and they have been known to swim far out into the sea. The body is covered with small, frequently granular scales; in the typically aquatic forms the body is slightly compressed laterally, and the ventral scales are scarcely larger than the others. Most of these ugly snakes inhabit the rivers of coasts of South-Eastern Asia and Papuasia; one, _Stoliczkaia_, is found in the Khasia Hills {607}of North-Eastern India; another, _Nothopsis_, lives far from its supposed allies, on the Isthmus of Darien, Central America.
_Acrochordus javanicus_ has no ventral shields. The head is flat, covered with small granules, with the eyes and nostrils on the upper surface. The general colour is dull olive-brown, lighter and spotted beneath. The food consists of fishes. Total length up to 4 feet.
_Chersydrus granulatus_ ranges from the coast of Madras to New Guinea. The body and tail are compressed, and form a ventral fold, covered with tiny scales like the rest of the body. General colour grey above, yellow below.
SUB-FAM. 2. COLUBRINAE.–The postfrontal bones are restricted to the posterior border of the orbits. The maxillary and dentary bones carry teeth on their whole length. The scales are usually imbricating. This sub-family contains the overwhelming majority of snakes, about 1000 species, all of them harmless so far as poison is concerned. None of them reach a great size, species of 6 or 7 feet in length being rare, e.g. _Zamenis mucosus_, but a few species of the Indian genus _Zaocys_ s. _Coryphodon_ grow to 10 feet. Most of the Colubrine snakes are oviparous, but some, e.g. _Coronella_, are viviparous. Some are aquatic, or semi-aquatic, others are absolutely arboreal, others again prefer dry, sandy, or rocky localities, according to their food. The distribution of the sub-family is cosmopolitan, finding its natural limits only in the permanently frozen under-ground, a condition which makes hibernation impossible. Most of them love warmth and like to bask, although many are not fond of the broiling sun. In the temperate regions they hibernate. As a rule they are intelligent and some of them become even affectionate.
_Tropidonotus._–The teeth form closely set series on the whole length of the maxillaries, palatines, pterygoids, and the greater portion of the dentaries. The premaxilla is toothless. The teeth of the maxillaries gradually increase in length, the posterior teeth being the longest. The pupil is round. There is a pair of internasal shields. The scales covering the body have each an apical, sensory pit, are mostly keeled, and are arranged in longitudinal series. The ventral shields are broad; the sub-caudals form two rows. This genus, with more than seventy species, has a wide range, practically over the whole world with the exception of New Zealand and the southern half of Australia.
{608}_T. natrix_, the common Grass-Snake, has a divided, or double, anal shield. The strongly keeled scales of the body form nineteen rows. There are normally seven upper labials, the third and fourth of which border the eye. The usual colour of the Grass-Snake is olive-grey or brown above, with black spots and narrow cross-bands. The labials are white or yellowish, with black sutures. The belly is checkered black and white, more or less suffused with grey. There are several colour-varieties. The typical or northern form has a white, yellow, or orange collar, bordered behind by a black collar; the pale collar is sometimes faint or absent. The second variety, rather common in Spain and Portugal, although not the only form in the Peninsula, has no collar whatever, and these specimens are sometimes almost uniformly grey-green above. The third variety, common in South-Eastern Europe and in Asia Minor, has a well-marked collar and a yellowish streak along each side of the back. But there are also almost black specimens.
The usual length of an adult female Grass-Snake is about 3 feet, but very exceptional cases of more than 6 feet are on record; the males are smaller and more slenderly built. The range extends over the whole of Middle Europe, Algeria, West and Central Asia. It does not, however, occur in Ireland or Scotland. Its northern limit is the southern part of Sweden.
The Grass-Snake prefers moist, grassy localities, with the neighbourhood of water, chiefly on account of the food, which consists entirely of fishes and Amphibia, notably of frogs; tree-frogs are preferred to anything else; toads are occasionally eaten, but mice are never taken.
The Grass-Snake can climb trees or rather shrubs and is an accomplished swimmer, often spending much of its time in water for fishing purposes. The fish is caught by the belly and then generally swallowed on land. The Grass-Snakes appear in the spring and disappear in the autumn to hibernate in the ground. They pair, in England, in the month of May or June, usually on warm and sunny mornings. The eggs are laid from July to the end of August, mostly in rich vegetable soil, in heaps of weeds or in manure-heaps. Young snakes lay fewer eggs than old specimens, which sometimes produce more than three dozen at a time. The eggs are soft, whitish yellow, about one inch long, and soon stick together, so that the whole clump {609}can be taken up at once. As a rule the new-laid eggs do not contain any visible sign of the embryo, but it often happens that the snake has to delay oviposition, and then the embryos are more or less advanced. This is especially the case with recently caught specimens. The young are hatched in the late summer or in the autumn, and seem to live at first upon soft insects and worms. Curiously enough they are easily drowned when they fall into the water, even in a shallow tank. My tame snakes have often laid eggs between the stones in the greenhouse; the young throve well upon unknown food, but most of them met their fate in the water. When they are a few weeks old they are strong enough to take baby-frogs.
The Grass-Snake becomes very tame, learns to distinguish between different people, allows itself to be handled without hissing or without voiding the obnoxiously smelling contents of its cloaca and anal glands, will in time take the offered food from the hand, and will even crawl up the arm or sleeve and coil itself up contentedly. One of the finest specimens, quite green, without a trace of a collar, and with brownish-red eyes, I caught in the Guadiana, where it had been fishing in midstream. It swam towards the bank, dived, and hid itself at the bottom between rocks. This snake, a female, became very tame. It never hibernated, shed its skin regularly every few months, and grew within nine years from 35 inches to 42 inches in length.
The Grass-Snake is perfectly harmless: although hissing, and striking out furiously with its head, it never bites, not even when it is severely handled. Its only defence consists of the awful contents of the cloaca and the anal glands, the secretion of which smells of concentrated essence of garlic mixed with other indescribable odours. The wildest specimens I have ever met with inhabited a swamp with a little stream to the north of Oporto close to the coast. To my utter surprise some of them actually made for me, swimming along rapidly with the head erect, about 6 inches above the water, and darting forwards with widely opened jaws, but they did not bite. These and other kinds of allied snakes require to drink much and often. Occasionally they drink milk when this is offered them, but that they suck the udders of cows or the breasts of women is an idle fable.
{610}_T. viperinus._–The scales are strongly keeled and form twenty-one to twenty-three longitudinal rows. The third and fourth labials border the eye. The anal shield is divided. The eyes and nostrils are directed upwards instead of sidewards, in adaptation to the essentially aquatic habits of this species, which lives upon fishes and Amphibia. The general colour is grey to reddish brown, with a black zigzag band along the back and a lateral series of black, yellow-eyed spots. The belly is yellow or red, checkered with black.
[Illustration: FIG. 160.–_Tropidonotus sirtalis._ × ½.]
The Viperine Snake bears a general resemblance to the common viper. It inhabits France, Italy, Spain and Portugal, and Morocco. Very large specimens attain a length of nearly 3 feet, but the ordinary size of adults is 2 feet. This snake spends most of its time in the water, but it is often found on land, basking on the top of a low wall or on a low shrub. It is exceedingly common in Spain and Portugal, where it inhabits almost every ditch, any standing water or slow river. In the Alemtejo, when during the rainless and hot summer the small {611}rivers have nearly dried up, these snakes collect in great quantities in the remaining stagnant and muddy pools, and as the stock of suitable fish gets exhausted, are often reduced to a deplorably emaciated condition. By the month of August they have become so thoroughly aquatic that they cannot be kept alive in dry surroundings for twenty-four hours. Those which I collected generally died, apparently from some kind of cutaneous suffocation, during the night following their capture. Taken under other conditions they are very easily kept and tamed.
I once caught a Viperine Snake in a ditch whilst it was swallowing an eel of nearly its own length. Both were separated, and then put into a small bag together with other creatures, and no more attention was paid to them for several hours. When I opened the bag again, the snake, undisturbed by my incessant walking about, was again busily engaged in trying to get outside that same eel!
_T. sirtalis_ (Fig. 160) is one of the almost endless varieties of what is now known by the name _T. ordinatus_, of North and Central America.
_T. tesselatus_ is closely allied to _T. viperinus_, which it represents in South Germany, Italy, South-Eastern Europe, and Asia; but the scales form only nineteen rows, and the fourth, or fourth and fifth labials, border the eye. The usual colour is olive-grey with dark little spots, and with a dark chevron-shaped band behind the occiput. The lower parts are yellow or red checkered with black, hence the specific name.
_Zamenis._–The maxillary teeth are not closely packed; they increase slightly in size backwards, and the last two are often a little larger and separated from the rest by a diastema. The mandibular teeth rather decrease in size from before backwards, inversely with the upper teeth. The scales are smooth with apical pits; the sub-caudals form two rows. The eye is large, and has a round pupil. The range of this genus, with about thirty species, extends over the whole of the Periarctic region.
_Z._ (_Ptyas_) _mucosus_ (Fig. 161), the Rat Snake of India, extending from Transcaspia to Java, is a very common species, often seen in menageries. Its general colour is brown above, often with black cross-bands on the hinder part of the body and tail. The under parts are yellowish. The fourth and fifth labials border the eye. {612}The scales on the body form only seventeen rows. Another feature of this species is the prominent ridge of the back-bone, not only in half-starved but in well-conditioned specimens. The Rat Snake grows to a length of more than 7 feet, and is as ill-tempered as most species of this genus.
[Illustration: FIG. 161.–_Zamenis mucosus_ (Rat Snake). × ⅕.]
_Z. gemonensis_ s. _viridiflavus_ inhabits France, Italy, the Balkan Peninsula, and Asia Minor. Its coloration is very variable. In general it is either green above and yellow below, hence the appropriate name _viridiflavus_, or the ground-colour of the back is greyish or olive-yellow with brownish spots, which form more or less longitudinal rows on the trunk, but gradually pass into blackish continuous lines on the tail; the under parts are yellow or greenish white, often with many very small, dark specks. The scales form seventeen or nineteen rows; the anal shield is divided. There are two small postocular scales and one subocular; of the eight labials, the fourth and fifth border the eye. This species is very lively, attacks {613}and bites furiously, climbs well, and when suspended from branches can protrude half of its length in a horizontal direction. It eats any kind of Reptile, Bird, or Mammal it can master; small animals are swallowed directly, rats and moles are first killed by constrictions. Large specimens reach perhaps 6 feet in length.
_Z. hippocrepis_ is the representative species in the Iberian Peninsula and in North-Western Africa. It is rarely more than 4 feet long, and is very pretty, the ground-colour being reddish or olive-yellow with a row of large, dark brown, yellow-edged spots along the back. Two rows of smaller spots adorn the sides; where the dark spots are large, the pale ground-colour is restricted to forming rings around the spots, producing a pretty appearance. The under parts are yellow or orange, with black spots. On the head is a dark, pale-edged patch in the shape of a horse-shoe, a feature alluded to by the specific name. Structural characters are the possession of a row of little subocular scales, which completely separate the eye from the labials, the double anal shield, and the small and smooth scales on the body, which form generally as many as twenty-seven rows.
_Z. constrictor._–The American Black Snake. The scales are smooth, and arranged in seventeen rows; the anal shield is divided. The general colour above is uniform bluish-black; below slaty, tinged with blue; the chin and throat are silvery white, sometimes with a black spot. Large specimens attain a total length of 6 feet.
Holbrook gives the following exhaustive account of this species, about which many sensational stories are current even in would-be scientific periodicals:–
The "Black Snake" is one of the commonest of North American species. It is extremely active, climbing with facility, and running with great rapidity, whence it is not uncommonly called the "Racer." It frequents shady places, covered with thick shrubs, on the margins of water. It feeds on mice, toads, or small birds; and, as it is an excellent climber, is frequently seen on trees in search of birds' nests. It is a bold and daring serpent, enters barns and out-houses without fear, and has been known to destroy young chickens. Its specific name _constrictor_ would imply that it suffocates or crushes its prey, but this according to Holbrook is at least doubtful. In the {614}breeding season it is extremely irascible, and will frequently attack persons passing at a distance of several steps; the tail then quivers with rage, making a quick vibrating motion, which in forests and among dead leaves sounds not unlike the Rattle-Snake; it now elevates the head one or two feet from the ground, and darts upon its adversary; luckily its bite is harmless, and not more painful than the scratch of a pin.
"It will even descend from trees to attack its enemy if teazed, yet it does not twine itself around the legs, as is commonly supposed.
"The same power of charming its prey has been attributed to the Black as to the Rattle-Snake, and with still less appearance of reason; for this is a nimble animal, and can pursue its prey, while the Rattle-Snake must lie in wait for his. It is remarkable that the birds most commonly found 'charmed' are the Cat-bird (_Turdus carolinensis_) or red-winged Black-bird (_Icterus phoeniceus_). These birds choose thick and shady places on the margins of streams for their residence, and generally build their nests on such shrubs as the alder; the latter bird not unfrequently takes the precaution to select such bushes as are on small islands, or such as have their roots surrounded by water, and thus their home is more secure. Now the Black Snake chooses precisely the same localities, knowing probably the haunts of its prey. The serpent begins the war by besieging the nest; the old bird, aware of its intention, attacks it with fluttering and uncertain motions, accompanied by a plaintive cry of distress, and is then said to be 'charmed.' The snake is at last either driven off, or it captures the young and not unfrequently the old bird too.
"Sometimes the old bird, by her cries, calls in the assistance of her neighbours to drive away the aggressor. I have seen more than a dozen birds thus engaged with a large Black Snake that had probably just committed some depredation, but was now quietly stretched on a rock, basking in the sun; and it was not a little singular that birds of very different genera, and those seldom seen together, all united in this warfare against a common enemy, and finally compelled him to seek shelter among some low, thick shrubs, by the violence of their assault."
_Zaocys_, with about half-a-dozen species in South-Eastern Asia, is closely allied to _Zamenis_. _Z. carinatus_, of the Malay {615}Islands, grows to 10 feet in length; it is consequently one of the largest harmless Colubrine snakes. The scales form only sixteen to eighteen rows. The sub-caudals are double. The general colour above is dark olive, passing into greenish brown farther back. The under parts are yellowish; black and yellow posteriorly. The fifth and sixth labials border the eye.
[Illustration: FIG. 162.–_Zaocys carinatus._ × ¼.]
_Coluber._–The maxillary teeth are of equal size, but the anterior mandibular teeth are the longest. The head is distinct from the neck. The nasals are distinct; not fused with the loreals. The eye is rather large, with a round pupil. The scales, smooth or keeled, have apical pits; the ventrals are rounded or angulate laterally; the sub-caudals are double. They all lay eggs and constrict their food. Nearly fifty species in the Periarctic region.
_C._ (_Elaphis_) _quatuorlineatus_ s. _quaterradiatus_ inhabits Italy and South-Eastern Europe. It occurs also in the Southern Tyrol. The scales of this large snake, which grows to nearly 6 feet in length, are arranged in twenty-five rows, and are feebly {616}keeled. The anal is divided. Adult specimens have a yellowish-brown ground-colour with a pair of black streaks on each side of the back. A black line extends from the eye to the angle of the mouth; the under parts are yellow, mostly closely spotted with brown. This snake is good-tempered, and keeps well in captivity. They live on sparrows, mice, lizards, etc., and are very fond of eggs. Large specimens can swallow several fowls' eggs in succession; the crushed remains of the shells are later disgorged. This handsome snake climbs extremely well in search of birds and their eggs, and it is not afraid of the water. The prey is caught either with the teeth or by a rapid twist of the tail; in any case, the prey is always strangulated by the constriction of coils thrown round it. A sparrow thus secured is literally passed through the moving coils along the snake's body into a position convenient for swallowing. Hungry snakes catch and secure several birds or mice before eating them. My own specimens became almost affectionately tame, never attempted to bite, and took food from the hand.
_C. leopardinus_ is smaller, but is one of the handsomest snakes of Southern Italy, South-Eastern Europe, and Asia Minor. It is closely allied to the previously described species. The ground-colour is pale brown with a dorsal series of dark brown or reddish, black-edged, transverse spots, and a lateral alternating series of smaller black spots, or with two dark brown, black-edged stripes bordering a yellowish vertebral stripe; usually with a forked black mark on the occiput and nape. The under parts are white, checkered with black, sometimes with the latter colour prevailing.
_C. flavescens_ s. _aesculapii_ is the Aesculap-Snake, for which the almost unknown name of _longissimus_ has now been unearthed in deference to the fetish of priority. This snake is of an extremely graceful and slender build, with a very long tail. Its home is the South of France, Italy, and South-Eastern Europe. It occurs sporadically in the Tyrol, for instance near Bozen, in Austria, at Baden near Vienna, in Germany only in the Taunus, especially at Schlangenbad, which has received its name from the frequent occurrence of this snake. This sporadic distribution favours the idea that these snakes were introduced by the Romans as inmates of the temples erected to Aesculapius at such watering-places. Specific characters are the smooth and shiny scales, {617}which are arranged in twenty-one to twenty-three rows, the distinctly angulate ventrals and the double anal and sub-caudals; the fourth and fifth of the upper labials border the eye, which has a round pupil. The coloration is very variable, as a rule olive-brown above with a dark streak behind the eye; the upper lips and a triangular patch on the temples are yellow; the under parts are uniform pale yellow. Some specimens are pale golden brown; others are very dark, almost black; while some have four darker stripes along the body, and lastly whitish specks occur on the upper surface. Large Aesculap snakes grow to a length of 5 feet. Their food consists chiefly of mice. They become very tame, although many of them at first bite furiously. Their climbing capacities are astonishing, the snakes being able to scale high and vertical walls provided there is the slightest "foothold." Some of my specimens escaped in the room and were at last found near the ceiling, resting on the rods of the curtains, up the folds of which they had managed to wriggle. Boulenger kept one for many years in a glass cage, where the snake entwined himself round the branches of a stick and allowed us to take him with the stick out of its socket and to inspect him. Being kept in an inhabited room, the snake did not exactly hibernate, creeping into the moss at the bottom of the cage; but it refused to feed, and remained in a rather drowsy condition coiled up on its favourite stand. During the pairing season they frequently resort to the water, at Schlangenbad at least; the few eggs are deposited under dry moss or in dry, decayed wood, and are hatched in about six weeks.
_C._ (_Rhinechis_) _scalaris_ has the smooth scales disposed in twenty-seven rows. The snout is strongly projecting, and has a V-shaped dark mark on the top; a black streak runs through the eye, and another black spot lies below the eye. Young specimens are pale brown with a series of dark H-shaped marks on the back, suggesting a ladder, hence the specific name. In the adult these marks are replaced by a pair of brown stripes running along the back; the under parts are always uniform yellow. Total length about 3 feet. This snake is restricted to the Iberian Peninsula and to the South of France. Most specimens are very ill-tempered. The young live upon locusts and small lizards, the old eat mice and small birds. In captivity they also take dead animals–a rare habit with snakes.
{618}_Dendrophis_ with about ten species inhabits South-Eastern Asia and Australia. They are typical Tree-Snakes. The scales are keeled, and form only thirteen or fifteen rows; those of the vertebral row are enlarged; the ventrals have a pair of suture-like lateral keels and a notch on each side, arrangements which are of great assistance in climbing, these snakes being able to slide up the branches of trees in almost straight lines instead of having to twist and undulate their way up.
[Illustration: FIG. 163.–_Dendrophis punctulatus._ × ½.]
_D. punctulatus_, of Northern and Eastern Australia, is olive-brown above, uniform or with black edges and yellow outer borders to the scales. The upper lips, the throat and anterior ventrals, are yellowish. Total length up to 6 feet.
_Leptophis_ is a Neotropical genus of Tree-Snakes. The body and the extremely long, whip-like tail are very slender. The head is very distinct from the neck; the eye is large, with a round pupil. The scales form thirteen or fifteen rows; the ventrals are sometimes angulate laterally; the sub-caudals are double. _L._ (_Ahaetulla_) _liocerus_ is a beautiful snake, green above {619}with a golden lustre, while the under parts are yellow or white. The total length of this species amounts to 6 feet, the tail then being nearly 2 feet long. These graceful Tree-Snakes live upon small reptiles and birds and their eggs. When shaken out of a tree or frightened off they let themselves fall down from considerable heights, coiling body and tail like a watch-spring, and alighting on the ground upon the spiral, which breaks the fall.
[Illustration: FIG. 164.–_Leptophis liocerus._ × ½.]
_Coronella._–The teeth are nearly all of equal size and form continuous series. The scales are smooth and have apical pits; the sub-caudals are double. The head is scarcely distinct from the neck. The pupil is round. This genus, with nearly twenty species, is widely distributed except in the Australian region, the northern half of Asia, and South America. We can mention only the two European species, one of which occurs in England.
{620}[Illustration: FIG. 165.–_Coronella laevis_, Smooth Snake (left), and two _Vipera berus_, Common Viper (right). × ½.]
{621}_C. austriaca_ s. _laevis_, the Smooth Snake. The scales are arranged in nineteen rows. Mostly the third and fourth labials border the eye. The anal shield is divided. The general colour is brown or reddish above, often with one or two lighter stripes, with small dark brown or red spots; two dark brown or red stripes on the nape, usually confluent with a large dark patch on the occiput; a dark streak extends from the nostril through the eye to the angle of the mouth. The under parts are red, orange, brown, grey or blackish, either uniform or speckled with black and white. The coloration is, however, subject to much variation, and some specimens strikingly resemble some of the Common Viper, which is also very variable in its coloration. The resemblance is enhanced when the Smooth Snake broadens its head by widening the jaws, as it is in the habit of doing. Two such similarly coloured specimens are represented in Fig. 165. On closer inspection the differences are great enough, the harmless snake having smooth scales, and the top of the head being covered with large shields; while the Viper has keeled scales, the top of the head being covered mostly with scales, a vertical (not round) pupil, and, moreover, when attacked, usually coils itself into a spiral disc with the head standing out in the middle, ready to strike. However, these two species are sometimes mistaken for each other.–The Smooth Snake prefers lizards as food to anything else, but it also takes mice. The prey is hunted chiefly in the late afternoon and in the evening, and is constricted by the coils of the snake. When caught or even when handled after months of captivity, the Smooth Snake bites deliberately and firmly, selecting a suitable spot, for instance a finger, opens the mouth widely and almost chews the spot. The bite is of course quite harmless, and scarcely draws blood, few of these snakes attaining a length of more than 2 feet. They are viviparous, bringing forth about half-a-dozen young at a time. The range of the Smooth Snake extends over the greater part of temperate Europe, from England and the Iberian Peninsula to Berlin, and south-eastwards to Asia Minor. In England it occurs in a few counties only, for instance in Hampshire and in Dorsetshire.
_C. girondica_, of the South of France, Italy, the Iberian Peninsula and North-Western Africa, much resembles the English Smooth Snake, from which it differs in a few points only. The scales are arranged in twenty-one, rarely in nineteen, rows; usually the fourth and fifth labials border the eye; and the rostral {622}shield, covering the end of the snout, is much broader than high. The coloration is variable, but there is always a pair of elongated blackish spots or a U-shaped mark on the nape.
SUB-FAM. 3. RHACHIODONTINAE.–With only a few teeth on the posterior part of the maxillaries, on the palatines and dentaries. Some of the vertebrae in the region of the lower neck have strongly developed hypapophyses, which are directed forwards and pierce the oesophagus. They are used for filing through or breaking the birds' eggs which seem to be the chief food of these snakes.
[Illustration: FIG. 166.–_Dasypeltis scabra._ × ½.]
_Dasypeltis scabra_, the only species, inhabits Tropical and South Africa; although it reaches scarcely more than two feet and a half in length, such a specimen is able to swallow an ordinary fowl's egg. Pigeons' eggs are swallowed by snakes little more than one foot in length, which seems at first sight quite impossible. The swallowed egg distends the skin to its utmost capacity; it then slides down further, the snake makes some slight contortions and the swelling collapses; after a while the broken and sucked-out shell is vomited out as a crumpled up {623}mass. Miss Durham has illustrated this curious process in a series of drawings.[190]
SERIES B. OPISTHOGLYPHA.
One, or a few, of the posterior maxillary teeth have a groove or furrow in front, which conducts the secretion of the enlarged upper labial glands. Apparently all these snakes are more or less poisonous, paralysing their prey before or during the act of deglutition. So far as man is concerned they are rather harmless, since the poison is not very strong, not available in large quantities, and above all because the small poison-teeth stand so far back that the snakes cannot easily inflict wounds with them.
The Opisthoglypha are of considerable morphological interest, since they connect the Colubridae with the Viperidae, the characteristic poisonous apparatus of which seems to have been derived from that of the Opisthoglypha by the reduction or shortening of the anterior portion of the maxillaries and the harmless teeth, so that the posterior or poison-fangs come to the front.
The Opisthoglypha comprise about three hundred species and are cosmopolitan, including Madagascar but excepting New Zealand. They contain truly terrestrial, arboreal, and thoroughly aquatic forms.
SUB-FAM. 1. DIPSADOMORPHINAE.–The nostrils are lateral and the dentition is well developed. Long-tailed, terrestrial, and arboreal forms. Most of the arboreal species are green above, often with white or yellow longitudinal bands, while the under parts are white or yellow. They feed chiefly upon lizards, birds and their eggs.
_Dipsadomorphus_ s. _Dipsas_ (part).–Typical, very long-bodied and long-tailed Tree-Snakes, with a vertical pupil. The median or vertebral row of smooth scales is enlarged; the broad ventral scales are bent at an obtuse angle on the sides, the resulting ridge assisting in climbing. The sub-caudals are arranged in two rows. Ten to fourteen maxillary teeth are followed by two or three enlarged, grooved fangs.
_D. trigonatus_, of India, grows to one yard in length. Yellowish olive or pale grey above, with a white, black-edged {624}zigzag band along the back, or with a series of white, black-edged spots.
_D. cyaneus_, of Northern India, Assam, etc., is a beautiful Tree-Snake, green above, with the skin between the scales black, uniform greenish yellow below. Total length up to 4 or 5 feet.
_Dipsas_ e.g. _D. bucephala_.–Maxillaries with eleven or more teeth. Pterygoids toothless. Body strongly compressed, with thirteen rows of smooth scales; the vertebral row enlarged; sub-caudals double; tail very long. Tropical South America.
_Leptognathus_ with many species in Central and South America, like _Dipsas_, but with teeth on the pterygoids.
_Coelopeltis._–Terrestrial and diurnal, with a round pupil. The row of small maxillary teeth is followed by one or two much larger, grooved fangs situated at a level below the posterior border of the eye. The first half-a-dozen mandibular teeth are much larger than the rest. The scales of the adult are more or less distinctly grooved longitudinally, hence the generic name, and are arranged in seventeen or nineteen rows. The sub-caudals form two rows; the ventrals are rounded off laterally. Two species in the Mediterranean countries and in South-Western Asia.
_C. monspessulana_ s. _lacertina_ is one of the largest snakes in Europe, reaching a length of 6 feet, of which the tail takes up 18 inches. Olive-brown or yellowish or reddish above, frequently with small, dark, light-edged spots. The sides are often blackish, with whitish specks. The under parts are yellowish white, with or without brownish markings. Some specimens are very green, with a dull blackish neck. One of the specific names of this terrestrial snake is the latinised form of Montpellier; the other refers to the shape of the head, which is not unlike that of a lizard, partly owing to the concave forehead. This species inhabits rather dry localities studded with shrubs, where it hunts for lizards, birds, and mice. It is sure to attract notice by its loud hissing when it is disturbed. When driven into a corner it strikes out furiously, but does not, as a rule, bite. I have caught some which after a few days became quite gentle. Small animals become torpid a few minutes after they have been bitten.
_Macroprotodon cucullatus_ occurs in Andalucia, the Balearic Islands, and in North Africa. The dentition is peculiar. The {625}fourth and fifth maxillary teeth are enlarged, followed by an interspace, then follow several small teeth, and lastly the two enlarged, grooved teeth. The sixth mandibular tooth is very long, separated by a space from the much smaller posterior teeth. The general colour of this sand-loving snake is pale brown or grey above with small spots or streaks on the trunk, and with a large black patch behind the head extending over the sides of the neck, hence the specific name. The under parts are bright red or yellowish, sometimes spotted with black. Total length under 2 feet.
SUB-FAM. 2. ELACHISTODONTINAE.–With only a few teeth on the posterior part of the maxillary and dentary bones, and on the palatines and pterygoids. Some of the vertebrae in the thoracic region have much-developed unpaired hypapophyses, which are directed forwards and pierce the dorsal wall of the gullet. In this respect _Elachistodon westermanni_, of Bengal, the only species, bears a striking resemblance to the South African Aglyphodont _Dasypeltis_ (see p. 622), and it is probable that this apparently very rare Indian snake also swallows eggs. It is brown above, with a yellowish vertebral stripe; yellowish below.
SUB-FAM. 3. HOMALOPSINAE.–The nostrils of these absolutely aquatic and viviparous snakes are valvular, and are situated on the upper surface of the snout. The eyes are small with vertical pupils. The two dozen species, mostly very ugly, inhabit the rivers and estuaries of the East Indies from Bengal to North Australia. Some species have very small and narrow ventral scales, recalling the Hydrophinae, or the burrowing snakes, none of which use their ventral scales for locomotory purposes.
_Homalopsis buccata_, _Cerberus rhynchops_ and _Hypsirhina_, e.g. _H. plumbea_, have well-developed ventral scales; the other scales of the first two genera are keeled, those of the third are smooth. In _Hipistes_ the whole head is covered with very small scales; all the scales of the body are smooth except the very narrow ventrals, which have double keels. _H. hydrinus_, of Siam and the Malay Peninsula, has a compressed body, and in its general appearance much resembles the Hydrophinae. It lives, like its allies, upon fishes, and it swims far out into the sea.
SERIES C. PROTEROGLYPHA.
The anterior maxillary teeth are deeply grooved, or so folded {626}as to appear hollow or perforated. Behind these enlarged poison-fangs the maxilla carries a series of smaller, solid teeth; hence the term "proteroglyphous," which means that the anterior teeth are grooved, in opposition to "opisthoglyphous." Both series have been developed independently.
The Proteroglypha are all extremely poisonous, mostly viviparous, and widely distributed over the whole of the Australian, Palaeotropical and Neotropical regions, with the exception of Madagascar and New Zealand; they extend northwards into the warmer parts of North America, and they also range over a great portion of the Palaearctic sub-region, being found in North Africa and South-Western Asia. They form two natural sub-families: Elapinae, with cylindrical tails, and Hydrophinae or Sea-Snakes, with laterally compressed tails.
SUB-FAM. 1. ELAPINAE.–The tail is cylindrical. The Elapinae comprise nearly 150 species, which have been grouped into a great number of, mostly somewhat imaginary, genera. In Australia they constitute the great majority of Snakes, there being besides the deadly Elapinae only a few Pythons and Typhlopidae, and very few Colubrinae.
[Illustration: FIG. 167.–Map showing the distribution of the Elapine Snakes.]
_Naja._–The pair of large and grooved poison-fangs are separated by an interspace from one to three small, faintly grooved teeth near the posterior end of the maxillaries. The scales are smooth and without pits, and are arranged in fifteen to twenty-five oblique rows on the trunk, although more occur in the region of the neck; the vertebral row is not enlarged. The head is but slightly distinct from the neck. Each nostril lies between two nasals and the internasal. The sub-caudals form two rows. The pupil is round. The neck-region can be expanded {627}into a hood by the spreading and moving headwards of the ribs. Several species in Southern Asia and in Africa.
[Illustration: FIG. 168.–_Naja tripudians_ (the Cobra). × ⅕.]
_N. tripudians_ (the "Cobra").–The coloration varies much. The typical form is yellowish to dark brown with a black and white spectacle-mark on the dorsal side of the hood, and with a large black and white spot on each side of the corresponding under surface. Other specimens are uniform pale brown to blackish grey, without any markings on the hood. The Cobra is widely distributed, from Transcaspia to China and to the Malay Islands; in the Himalayas it ascends to about 8000 feet above the level of the sea. Very large specimens are said to attain more than 6 feet in length, but a cobra of 5 feet, inclusive of the tail of 9 inches, is considered large. The Cobra prefers places which afford it a convenient hole to retire into; for instance, deserted hills of termites, ruins, heaps of stones and stacks of wood, and it has the disagreeable habit, like the harmless Rat-snake, _Zamenis mucosus_, of making itself at home in inhabited houses, probably attracted by the rats. Its chief food consists of small Vertebrates;–frogs, lizards, rats, occasionally fishes and {628}small birds. It drinks much, and hunts chiefly in the late afternoon and in the evening, although it possesses a round pupil. It avoids hot sunshine. Many observations show that the cobras live in pairs, otherwise they do not take much notice of each other or of other kinds of snakes. The female lays about a dozen soft-shelled eggs as large as those of pigeons.
This cobra is used by Indian conjurers. The "dance" is the habit of these snakes of erecting themselves, when agitated, upon the hinder third or quarter of their length, whilst they spread out the hood and sway the head and neck to the right and left, always in an attitude ready for striking. They are docile and by nature not vicious. Most of the performing cobras have their teeth drawn, and they then know well that they cannot bite. They only strike at the hand, just as uninjured specimens soon avoid biting into the iron rod with which they are lifted up in menageries. The drawing of the teeth is an operation which has to be repeated, since reserve-teeth soon take the place of the lost pair.
I cannot refrain from relating an abstract of a ridiculous episode which happened in the Munich Aquarium in the year 1882. One of six specimens of the African species _Naja haje_ was missing. The police closed the establishment, which during the following eight days was turned inside out without any other effect than that two other, harmless, snakes were discovered. Twice the building was fumigated with sulphur, until the Cobra was at last found suffocated, fifteen days after the beginning of the search. This snake caused the owner of the Aquarium a loss of nearly £1500. But the cruel joke was, that during the commotion the man who had collected and sold the six snakes declared upon oath that their teeth had been so well drawn and the germs of possible reserve-teeth had been so thoroughly destroyed that the snakes were rendered absolutely harmless. But he was not believed, in spite of a commission of professors and doctors appointed, who experimented upon the remaining five Cobras with sulphur and did not find any poison-fangs, "although the mouth was probed and poked into as far down as the larynx."
Cobras have quite a number of enemies. Peafowl and Jungle-cocks are said to be partial to young snakes; pigs eat them greedily, and are to a certain extent immune against {629}their bite. The same applies, according to the most recent observations, to the famous Mongoos. Sir E. Tennent, in his _Natural History of Ceylon_, quoted several times in the present book, makes the following remarks about the immunity of this little creature:–
"I have found universally that the natives of Ceylon attach no credit to the European story of the Mongoos (_Herpestes griseus_) resorting to some plant, which no one has yet succeeded in identifying, as an antidote against the bite of the venomous serpents on which it preys. There is no doubt that, in its conflicts with the cobra and other poisonous snakes, which it attacks with as little hesitation as the harmless ones, it may be seen occasionally to retreat, and even to retire into the jungle, and, it is added, to eat some vegetable.... A number of plants, such as the _Ophioxylon serpentinum_ and _Ophiorhiza mungos_, the _Aristolochia indica_, the _Mimosa octandria_, and others, have each been asserted to be the Ichneumon's specific.... If the Ichneumon were inspired by that courage which would result from the consciousness of security, it would be so indifferent to the bite of the serpent, that we might conclude that, both in its approaches and its assault, it would be utterly careless as to the precise mode of attack. Such, however, is far from being the case; and next to its audacity, nothing can be more surprising than the adroitness with which it escapes the spring of the snake under a due sense of danger, and the cunning with which it makes its arrangements to leap upon the back and fasten its teeth in the head of the cobra. It is this display of instinctive ingenuity that Lucan celebrates where he paints the Ichneumon diverting the attention of the Asp by the motion of his bushy tail, and then seizing it in the midst of its confusion. See _Pharsalia_, lib. iv. verses 729-734."
There is a widespread belief in the efficacy of "Snake-stones," which are generally pieces of charred bone, well polished, occasionally pieces of chalk or some similar porous substance, which, if pressed upon the bleeding wound, are supposed to absorb the poison. Snake-charmers profess to prepare such "stones," and to preserve the composition as a secret. The manufacture is a lucrative trade. The Boers bought them, imported from India, at high prices. Mr. Selous saw one, or heard of one, that was kept as an heirloom. Snake-stones are {630}also made, and used, in Mexico, of charred hartshorn; they are called "piedras ponsonas."
The use of the Snake-stone, called "Pamboo-Kaloo," has probably been communicated to the Singhalese by the itinerant snake-charmers who resort to the island from the coast of Coromandel.
Although Sir E. Tennent describes several instances of the successful application of snake-stones as well authenticated, he has never himself been an eye-witness. Although two cases have been fully described, they do not at all exclude the possibility, nay the probability, that the Tamils imposed upon the Europeans in order to sell the snake-stones.
"No doubt the snake-stones, owing to their porous nature, adhered to the bleeding wound, became saturated with blood, and then fell off. Very likely, in case of a poisonous bite, some of the venom would be sucked up too, but we do not know if those snakes were still in the possession of their poison-fangs. Properly conducted experiments with snake-stones have proved as little efficacious as the application of dry cup.
"Theoretically snake-stones as quick absorbent agents of the blood with the poison are good; they will certainly prevent some of the poison from entering the system, but that would, at best, be a partial cure only.
"In March 1854 a friend of mine was riding, with some other civil officers of the Government, along a jungle path in the vicinity of Bintenne, when he saw one of two Tamils, who were approaching the party, suddenly dart into the forest and return, holding in both hands a Cobra de capello, which he had seized by the head and tail. He called to his companion for assistance to place it in their covered basket, but in doing this, he handled it so inexpertly that it seized him by the finger, and retained its hold for a few seconds, as if unable to retract its fangs. The blood flowed, and intense pain appeared to follow almost immediately; but with all expedition the friend of the sufferer undid his waist-cloth, and took from it two snake-stones, each of the size of a small almond, intensely black and highly polished, though of an extremely light substance. These he applied, one to each wound inflicted by the teeth of the serpent, to which they attached themselves closely; the blood that oozed from the bites being rapidly imbibed by the porous texture of {631}the article applied. The stones adhered tenaciously for three or four minutes, the wounded man's companion in the meanwhile rubbing his arm downwards from the shoulders towards the fingers. At length the snake-stones dropped off of their own accord; the suffering of the man appeared to subside; he twisted his fingers till the joints cracked, and went on his way without concern. Whilst this had been going on, another Indian of the party, who had come up, took from his bag a small piece of white wood, which resembled a root, and passed it gently near the head of the cobra, which the latter immediately inclined close to the ground; he then lifted the snake without hesitation, and coiled it into a circle at the bottom of his basket. The root by which he professed to be enabled to perform this operation with safety he called the "Naya-thalic kalanga" (the root of the snake-plant), protected by which he professed his ability to approach any reptile with impunity."
The following narrative, communicated to Sir E. Tennent by H. E. Reyne, of the Department of Public Works, Colombo, seems to exclude the possibility of deception:–
"A snake-charmer came to my bungalow in 1854, requesting me to allow him to show me his snakes dancing. As I had frequently seen them, I told him I would give him a rupee if he would accompany me to the jungle and catch a cobra that I knew frequented the place. He was willing, and as I was anxious to test the truth of the charm, I counted his tame snakes, and put a watch over them until I returned with him. Before going I examined the man, and satisfied myself he had no snake about his person. When we arrived at the spot, he played on a small pipe, and after persevering for some time, out came a large cobra from an ant-hill, which I knew it occupied. On seeing the man it tried to escape, but he caught it by the tail and kept swinging it round until we reached the bungalow. He then made it dance, but before long it bit him above the knee. He immediately bandaged the leg above the bite, and applied a snake-stone to the wound to extract the poison. He was in great pain for a few minutes, but after that it gradually went away, the stone falling off just before he was relieved. When he recovered he held a cloth up, which the snake flew at, and caught its fangs in it; while in that position, the man passed his hand up its back, and having seized it by the throat, {632}he extracted the fangs in my presence and gave them to me. He then squeezed out the poison on to a leaf. It was a clear oily substance, and when rubbed on the hand produced a fine lather. I carefully watched the whole operation, which was also witnessed by my clerk and two or three other persons."
_N. haje_ is the common hooded cobra of Africa, the "Aspis," so called on account of its shield or hood–the "Spy-Slange" of the Boers. As a rule the spectacle-marks on the neck are absent or indistinct, the general colour varies much, either brown above, yellowish beneath, with or without brown spots; or dark brown above with yellowish spots, dark brown beneath; or blackish above and beneath. The name Spy-Slange, meaning Spitting Snake, refers to the habit which this and other African Cobras have of letting the poison drop from the mouth like saliva when they are excited. This is not a
## particularly economical habit, nor is it of the slightest use to the snake.
_N._ (_Ophiophagus_ s. _Hamadryas_) _bungarus_ s. _elaps_ is the "Hamadryad" or "Snake-eating Cobra" or "King Cobra." It has a well dilatable hood; the very variable coloration is yellowish to black, with or without an olive gloss. Many specimens have more or less distinct dark cross-bands or rings around the body, while others are olive above with black-edged scales, and others again are very dark above and beneath. The distinctive, specific character is the small number of scales, these forming only fifteen rows on the middle of the body, nineteen or twenty-one on the dilatable neck. There is a pair of large occipital shields behind the parietals.
This snake reaches the length, enormous for a poisonous snake, of 12 feet or more. Its size and very poisonous nature make it the curse of the jungle. It ranges from India to South China, and to the Philippines. The food seems to consist entirely of other snakes.
_Sepedon haemachates_ is another hooded snake in South Africa, where it is known as the "Ringhals," _i.e._ banded neck. It differs from _Naja_ by the absence of small teeth on the maxillaries behind the fangs, and by the strongly keeled scales, which form nineteen rows. The general colour is black above variegated with yellow or pale brown; the under parts are also black, often with one or two whitish bands across the lower portion of the neck.
{633}The Rev. G. Fisk[191] mentions the case of two young "Ringhals," of 10 and 9 inches in length, having been attacked and partly devoured by a mouse, supposed to be _Dendromys melanotis_, which was put with the snakes in a band-box. On the habits of the Ringhals see Symonds.[192]
[Illustration: FIG. 169.–_Sepedon haemachates_ (the "Ringhals"). × ⅕.]
_Bungarus._–The scales are smooth, and form thirteen to seventeen rows. The spine is very prominent, and the median row of scales which covers the ridge is much enlarged. There is no dilatable hood. In other respects _Bungarus_ is closely allied to _Naja_; about half-a-dozen species, in South-Eastern Asia.
_B. fasciatus_ reaches a length of 5 feet. The general colour is bright yellow, alternating with blackish rings.
_B. coeruleus_ s. _candidus_ is the dreaded "Krait," occurring in the whole of the Indian sub-region. It is dark brown or bluish black with narrow cross-bars or white specks, or it is alternately barred brown and yellow; the under parts are uniform white. Total length rarely 4 feet.
The "Krait" seems to cause more deaths in India than any other snake, since it is very common, especially in Bengal and in {634}Southern India, and often creeps into the houses. It lives chiefly on rats, lizards, and snakes.
_Callophis._–With only thirteen rows of smooth scales. The head is small, not distinct from the neck. The small eye has a round pupil. The short tail has two ventral rows of scales. The whole body is cylindrical. Several small species, one or two feet in length, in South-Eastern Asia. _C. macclellandi_ in India and Indo-China is reddish brown above, yellow below, with regular, equidistant, black, light-edged cross-bands or rings. Total length up to 2 feet.
_Doliophis_ differs from _Callophis_ mainly by the enormously developed poison-glands which, instead of being restricted to the head, extend along the anterior third of the body, gradually thickening, and terminating in front of the heart with club-shaped ends. Owing to the extension of these glands, which can be felt through the skin as thickenings at the end of the first third of the body, the heart has been shifted farther back than in any other snake. Several species in Indo-China and in the Malay Islands, _D. intestinalis_ with many colour-variations.
Australia suffers from an abundance of Elapine snakes, of which we will mention only the three commonest.
_Pseudechis_ e.g. _Ps. porphyriaceus_, the "Black Snake" of Australia, has seventeen rows of smooth scales on the body, a few more on the neck, which however is not, or is only slightly, dilated. A few of the sub-caudal scales are undivided, the rest are paired. The head is distinct from the neck; the pupil is round. Total length up to 5 or 6 feet. The general colour above is black, with the outer row of scales red at the base; the ventral scales are red with black edges. The females are generally more brown than black, and are therefore sometimes known as "Brown Adders." They live on small mammals, birds, lizards and other snakes.
_Notechis scutatus_ s. _Hoplocephalus curtus_, the "Tiger Snake," has rather small eyes with round pupils. The head is distinct from the cylindrical body, which is covered with fifteen to nineteen rows of smooth scales. The sub-caudals are single. The head of this variably coloured snake is mostly black, the body olive brown with dark cross-bands; towards the tail the coloration becomes more uniformly blackish. The under parts are pale {635}yellow. The range of this very common snake extends over Tasmania and Australia.
_Acanthophis antarcticus_, the "Death Adder," is easily recognised by the peculiar tail, the end of which is laterally compressed, beset with a few rows of enlarged imbricating scales, and terminates in a thin horny spine. The head is distinct from the neck, and flat; the eye has a vertical pupil. The short and thick body is covered with twenty-one or twenty-three rows of keeled scales. The anterior caudals are single, the posterior double. The colours of the upper parts are a mixture of brown, reddish and yellow, with dark cross-bands. The belly is pale yellow, often spotted with brown or black. The end of the tail is yellow, reddish brown or black. The total length of this stout and ugly viviparous creature remains under 3 feet. It is widely distributed from South Australia to the Moluccas. The use of the peculiar tail very probably consists in attracting or fixing the attention of small animals; the snake, lying coiled up on a dry and sandy spot, slightly raising and vibrating the tip of the tail.
_Elaps_ is an entirely American genus, with many species, most of which are extremely prettily coloured, red and black in alternate rings being a favourite pattern. The maxillaries carry no teeth behind the poison-fangs. The scales of the body are smooth and form fifteen rows. The tail is short. The small eye has mostly a vertical pupil. The head is very small, not distinct from the neck. The squamosal and quadrate bones are short, and the gape of the mouth is so limited that these beautiful snakes, although possessing strong poison, are practically harmless to man. One of the prettiest is _E. corallinus_ of the forests of Tropical South America and the Lesser Antilles. The whole body, above and below, is adorned with about twenty deep black rings, which are edged with yellow and again separated by red rings equalling in width the black ones. Sometimes the red rings are dotted with black, and the black dots may form additional rings between the red and the yellow. Total length under 3 feet.
SUB-FAM. 2. HYDROPHINAE (Sea-Snakes).–The tail is strongly compressed, sometimes the body also. All the scales are small, and there are often no enlarged ventrals. The eyes are small, with round pupils. All these snakes are very poisonous and live in the sea, often at considerable distances from the land, {636}with the exception of one species of _Distira_, _D. semperi_, which is confined to the land-locked freshwater Lake Taal at Luzon in the Philippines. They live on fish, and range from the Persian Gulf to Central America. In conformity with their absolutely aquatic life they are viviparous, and they die when kept out of the water for any length of time. About fifty species are known.
_Enhydrina valakadien s. bengalensis_ has scales with a small tubercle or keel, which is stronger in the males; the ventrals are very small, forming a scarcely enlarged series. The maxillaries carry two or more small grooved teeth in addition to the poison-fangs. The back is olive or dark grey, with black transverse bands, which are most distinct in the young. The under parts are white. This species ranges from Persia to the Malay Islands.
[Illustration: FIG. 170.–_Enhydrina valakadien_ (left upper figure) and _Hydrophis obscura_ (right lower figure). × ¼.]
_Hydrophis_ e.g. _H. obscura_.–The body is long; the head and neck are very slender, the body becoming much thicker farther back. The small teeth behind the poison-fangs are not grooved. The ventral scales are very small, the others are keeled, strongly so {637}in the males. The general coloration of this Sea-Snake, which reaches about one yard in length, is dark olive-green above with yellowish cross-bars, which form complete rings round the slender part of the body. Other specimens are pale olive, with dark cross-bands. This species occurs in the Bay of Bengal and the Malay Archipelago.
As a rule Sea-Snakes are not found in mid-ocean. After leaving Ceylon, the steamer meets them again in the Straits of Malacca. Those which occur near the south coast of Japan, e.g. _Distira cyanocincta_, are found there only in the summer, and are probably carried there by the south-west monsoon.
According to Semper the gravid female visits the shores of low islands, there to give birth to its young between the rocks, and she remains with her offspring for some time. Semper once found a large female, probably _Platurus fasciatus_ s. _colubrinus_, coiled up amongst rocks, and between the folds were at least twenty young, each already about 2 feet long.
Boulenger[193] has written an interesting popular account of Sea-Snakes.
FAM. 8. AMBLYCEPHALIDAE.–Some thirty species of Neotropical and Oriental Snakes have been separated from the Colubridae on account of the pterygoids, which are widely separated from the quadrates, the posterior ends of the pterygoids not reaching beyond the level of the occipital condyle. This condition can be ascertained when the mouth is opened widely. The prefrontals are not in contact with the nasals. The squamosals are reduced to pad-like vestiges. Externally the Amblycephalidae are easily distinguished from the Colubridae by the absence of a longitudinal median mental groove. The head is thick, very distinct from the neck, and gives these harmless snakes a "poisonous" appearance. The pupil is vertical.
_Amblycephalus_, e.g. _A. monticola_.–Maxillaries short, with only five or six teeth. Sub-caudals in two rows. Body compressed, covered with fifteen rows of scales. South-Eastern Asia.
FAM. 9. VIPERIDAE.–The maxillaries are very short, movably attached to the prefrontals and ectopterygoids, so that they can be erected together with the large poison-fangs, which (besides reserve-teeth) are the only maxillary teeth. The prefrontals are not in contact with the nasals. The squamosals are very loosely {638}attached. For further details see Fig. 180. The poison-fangs are perforated, having a wide hole on the anterior side at the base, in connexion with the large poison-gland; the hole leads into a canal, which opens gradually as a semi-canal on the anterior surface of the distal third or quarter of the tooth. As usual in poisonous snakes, several reserve-teeth are stowed away behind the acting fang. When the latter is broken off or has served its time it is cast off at the base, and the next reserve tooth takes its place. The supply of reserve-teeth is indefinite, half-finished teeth down to mere germs constantly growing.
All the Viperidae are very poisonous, and all, except the African _Atractaspis_, are viviparous. They include terrestrial, arboreal, semi-aquatic, and burrowing types. The family is cosmopolitan, excepting Madagascar and the whole of the Australian region; it is divided into Vipers and Pit-Vipers.
SUB-FAM. 1. VIPERINAE (Vipers).–There is no sensory external pit between the eye and the nose, and the maxillary is not hollowed out above. The Vipers are absolutely restricted to the Old World, ranging over the whole of Europe, Africa, and Asia, with the exception of Madagascar; their northern extension is limited only by the permanently frozen condition of the underground. Nine genera with about forty species are known.
[Illustration: FIG. 171.–Map showing the distribution of the Sub-Family Viperinae. Corsica and Sardinia should be black in the map.]
_Causus_ with a few species in Africa and _Azemiops feae_ in Upper Burmah are the only vipers which have the head covered {639}with large symmetrical shields, while in the other genera the head-shields are broken up into scales or small shields. _Causus rhombeatus_ is very common in Africa, from the Gambia to the Cape. It reaches a length of a little more than 2 feet. Pale olive-brown above, usually with a dorsal series of large rhombic or V-shaped dark brown, sometimes white-edged spots, and with a dark arrow-shaped mark on the occiput; under parts yellowish white or grey.
_Bitis_ s. _Echidna_.–Very much like _Vipera_, but the nasal shields are separated from the rostral by small scales, and the postfrontal bone is very large. Several species in Africa.
[Illustration: FIG. 172.–_Bitis arietans_ (Puff Adder). × ¼.]
The head is very distinct from the neck, chiefly owing to the large poison-glands and to its being, like the body, much depressed. The small eye has a vertical pupil, and is separated from the labials by a series of small scales. The scales are keeled, and form many, from twenty-nine to forty-one, rows; the tail is very short, with two rows of scales below.
In _B. arietans_, the "Puff Adder," the nostrils are directed upwards. This ugly brute is yellowish to orange brown above with regular, chevron-shaped dark bars or other markings, helping {640}to conceal the creature when it is lying on sandy and stony ground; the under parts are yellowish white. The Puff Adder reaches a length of 4, or very rarely 5 feet, ranging all over Africa, except the north coast, and extending into Southern Arabia. It is very slow, and trusts to not being discovered when lying in the dry grass; when approached it inflates the body and hisses loudly with a puffing sound, watches the enemy with raised and characteristically bent head and neck; but it bites only when actually touched or attacked. The effect of the bite is very dangerous. Its prey consists chiefly of small mammals, which are hunted during the night.
_B. (Echidna) nasicornis_, of Tropical West Africa, has two or three enlarged scales above the supranasals; they stand upon erectile tissue so as to form horn-like elevations. This "Nose-horned Viper" grows to a length of 4 feet, and is rather prettily marked; the ground-colour is purplish or reddish brown, with a vertebral series of large, pale, dark-edged spots and oblique crosses. The young are at birth as much as one foot in length, and are very tastefully coloured.
_Cerastes_ and _Echis_ prefer to burrow in sand. The lateral scales are smaller than the dorsals, and arranged obliquely with serrated keels, so that the snakes can cover themselves with sand by lateral shovelling motions of the sides of the body.
_Cerastes cornutus_, the "Horned Viper" of North-Eastern Africa, from Algeria to Arabia, extending also into Palestine, has the sides of the ventral scales bent angularly, with an obtuse keel on either side. Above each eye stands a large horny, spiky scale. The upper parts are pale yellowish brown, mostly with dark spots arranged in several longitudinal rows. The under parts are white. This, or perhaps _C. vipera_, which has no horns, is supposed to be the species which has become famous through the suicide of Cleopatra.
About twenty years ago a number of "Horned Vipers" were brought to the Zoological Gardens of London, and attracted attention by their unusually long horns. It was found that some wily Egyptian snake-catcher had tried to manufacture a new species by taking specimens of the hornless _C. vipera_ and inserting a pair of hedgehog's spines, pushing them upwards through the mouth.
The "Horned Viper" attains a length of two feet and a half. {641}In the daytime it is invisible, being buried in the sand with only the eyes, nostrils, and the "horns" appearing above the surface.
_Vipera._–The head is distinct from the neck, and is covered with small scales and a few larger shields. The eye is separated from the labials by scales; the nasals are in contact with the rostral shield or separated by one naso-rostral shield. The scales on the body are strongly keeled; they are in two rows on the short tail. This genus with about ten species ranges over Europe, Asia, and the greater part of Africa.
[Illustration: FIG. 173.–_Cerastes cornutus_, the "Horned Viper" (right), and _Vipera ammodytes_, the "European Nose-horned Viper" (left). × 1.]
_V. berus_, the Common European Viper (see Fig. 165, p. 620). The snout is not turned up at the end; between the small head-scales there is generally a pair of well-developed parietal and frontal shields. The scales of the trunk form twenty-one rows. The coloration is very variable, there being grey, brown, red, or black specimens in the same country, and the much-spoken-of black zigzag line along the back is so often indistinct that it is a character not to be relied upon. Usually the grey, yellowish, olive, brown or red ground-colour is set off by a dark zigzag band along the spine, and by a series of lateral spots; an oblique or St. Andrew's cross or two diverging bold streaks of dark brown or black are usually present on the back of the head, and there is a dark streak behind the eye. The under parts are grey, brown, or black, uniform or speckled; the end of the tail is usually yellow or red.
{642}[Illustration: FIG. 174.–Skin of Viper. × 1. (From White's _History of Selborne_.)]
According to Boulenger, who is making a special study of the individual variations of Vipers (concerning colour, scaling, number of vertebrae, etc.), some specimens are entirely black in the males through extension of the black markings, in the females through darkening of the ground-colour. Males are usually distinguishable from females by darker, deep black markings and lighter ground-colour. The females are mostly larger than the males. The largest specimen in the British Museum measures 700 mm. = 28 inches, but a viper 2 feet long may be considered a very large specimen. The Common Viper has a wide range, from Wales to Saghalien Island, and from Caithness to the north of Spain. It ascends the Alps to a considerable altitude, up to 6000 feet. J. Blum[194] has published an elaborate statistical account of the Viper in Germany, unfortunately confining himself strictly to the political frontiers. According to the map attached to his work, the Viper is common all over Germany with the exception of South-Western and parts of Middle Germany. It is absent in Alsace, the Bavarian Palatinate, Rhenish Prussia, Hesse, the northern half of Baden, Würtemberg, and Franconia, countries which, speaking broadly, have a warm subsoil, composed of Red Sandstone and Basaltic formation. As a rule the Viper prefers heaths, moors, and mixed woods with sunny slopes. Brambles, clumps of nettles, hedges, the edges of little copses, heaps of stones, are favourite places of retreat, affording shelter, holes, and the vicinity of mice, which form its chief sustenance. At harvest-time it is often found in cornfields, and it frequently hides in the sheaves. Vipers are fond of basking on certain spots, on the top of a stone, the stump of a tree, or a patch of sand: a shower of rain or even passing clouds drive them back into their holes. They are eminently nocturnal, when they regularly "beat" their district, biting and paralysing their prey before swallowing it. A fire kindled at night is sure to draw vipers near; the same applies to other vipers, for instance _Cerastes_, which appears in perplexing {643}numbers at the camp-fire. They cannot climb, and they avoid going into water. The pairing takes place as a rule from March to May, a number of individuals, mostly males, collecting around the females, and forming entangled lumps of snakes; parturition takes place in the following July and August. In exceptionally warm winters they have been known to pair in December, having left their winter-quarters. They hibernate for about six months, more or less according to the climate, congregating in great numbers, sometimes in dozens. With very rare exceptions Vipers do not take food in captivity, but prefer starving themselves to death. The bite is as a rule not fatal. The seriousness of the case depends of course upon many circumstances, as for instance the state of concentration of the venom, the position and depth of the bite, and last but not least upon the general condition of health of the victim. General depression aggravated by nervousness, weakness of the bitten limb, occasional breaking out of the wound, are of frequent and protracted occurrence. (See also p. 590.)
_V. aspis_ is a more southern and western European Viper, occurring from France to the Tyrol, and in Italy. The snout is slightly turned up at the end, and still more so in _V. latastei_ of Spain and Portugal. In _V. ammodytes_, of South-Eastern Europe, the raised portion is produced into a soft, scaly appendage (see the lower figure on p. 641). Vipers are sometimes unpleasantly common in certain localities. This was for instance the case at the drill-ground near Metz, and the military authorities paid a price for each viper delivered to them. The supply of the latter increased to an alarming extent until the German authorities discovered that a regular trade had been established across the frontier, and that the French Lorrainers were importing vipers briskly.
_V. russelli_, the "Daboia" or Russell's Viper, is one of the scourges of India, Ceylon, Burma, and Siam. The scales form about thirty rows on the body. The upper surface of the head is covered with small, imbricating, usually keeled scales. The general colour is pale brown above with three longitudinal series of black, light-edged rings, which sometimes encircle reddish spots. The under parts are yellowish white, uniform, or with small crescentic black spots. Total length up to about 5 feet. The poisoning symptoms are described on p. 590.
{644}SUB-FAM. 2. CROTALINAE ("Pit-Vipers").–With a deep cavity or pit between the eye and the nose, lodged in the hollowed-out maxillary bone. This pit is lined with a modified continuation of the epidermis, and is amply supplied with branches from the trigeminal nerve. It is undoubtedly sensory, but we do not know its function. A good anatomical account of this organ has been given by West.[195] Some of the Pit-Vipers have a rattle at the end of the tail; these are the Rattle-Snakes. The rattle is composed of a number of horny bells which fit into each other. The oldest or terminal bell is in reality the horny covering of the tip of the tail, and with each moult or shedding of the skin the youngest bell becomes loose, but is held by the new covering which has been developed in the meantime. There is thus produced an ever-increasing number of loosely-jointed bells, but now and then most or all the bells break off, probably when they are worn out, and a new set is gradually developed. Rattles with a dozen bells are, for instance, very rare. They naturally increase in bulk with the age of the snake, but the number of joints is no indication of the snake's age.
[Illustration: FIG. 175.–Rattle of Rattle-Snake. (From White's _History of Selborne_.)]
[Illustration: FIG. 176.–Map showing the distribution of the Sub-Family Crotalinae.]
Pit-Vipers have a very wide distribution. They are divided into four genera with about sixty species. Rattle-Snakes are {645}restricted to America, but other Pit-Vipers occur in North and South America and in the southern half of Asia.
_Ancistrodon._–Without a rattle. The upper surface of the head is covered with nine large shields, but the internasals and prefrontals are sometimes broken up into scales. The scales of the body have apical, sensory pits. About ten species, some in Central and North America, others in the Caspian district (_A. halys_), in the Himalayas (_A. himalayanus_), in Ceylon, Java, etc.
[Illustration: FIG. 177.–_Ancistrodon piscivorus_ (Water-Viper). × ¼.]
_A. piscivorus_ s. _Trigonocephalus cenchris_ (part), the "Water-Viper," inhabits North America from Carolina and Indiana to Florida and Texas. The general colour is reddish to dark brown, with darker cross-bands or with C-shaped markings; a dark, light-edged band extends from the eye to the angle of the mouth. The under parts are yellowish, spotted with black, or the latter is the prevailing colour. Total length up to 5 feet. The Water-Viper is semi-aquatic and lives chiefly on fishes, but it also eats other snakes and various Amphibia, Birds, and Mammals. This snake is very good-humoured in captivity, and becomes {646}easily tame. A gentleman in Berlin, rather too much addicted to making pets of poisonous snakes, had a pair which propagated regularly. When I was a boy he invited me to feed the young Water-Vipers with fishes cut into strips, and I enjoyed this immensely until he warned me not to touch the mother, which might bite strangers.
[Illustration: FIG. 178.–_Ancistrodon contortrix_ (Moccasin-Snake or Copper-head). × ¼.]
_A. contortrix_ s. _Trigonocephalus cenchris_ (part), the "Moccasin-Snake" or "Copper-head," is one of the few poisonous snakes which possess a loreal shield, _i.e._ a shield intercalated between the pre-oculars and the nasals; below it lies the pit. The general colour is yellowish to pink or pale brown, with dark brown or red cross-bars or triangular marks. The under surface is yellowish or reddish, speckled with grey or brown, and with a lateral series of large blackish spots. Total length of full-grown specimens about one yard. The Moccasin-Snake ranges from Massachusetts and Kansas to Northern Florida and Texas. It prefers swampy localities or meadows with high grass, where it hunts for small Mammals and Birds.
_Lachesis._–Without a rattle. The upper surface of the head is covered with very small shields or with scales. About forty {647}species in South-Eastern Asia and in Central and South America.
_L._ (_Bothrops_ s. _Craspedocephalus_) _lanceolatus_ inhabits nearly the whole of South America, extending into Mexico and the Lower Antilles, _e.g._ Martinique, Guadaloupe, and Santa Lucia, where it is known as the "Fer-de-Lance," and is the curse of the sugar-plantations on account of its being so very common and so deadly poisonous. The Mongoose was introduced as a possible antagonist, but the little Indian Mammal wisely left the dangerous reptile alone, and has in some places established himself as another pest–as a destroyer of poultry. The Fer-de-Lance grows to a length of 6 feet, establishes itself everywhere–in swamps, plantations, forests, in the plains and in the hills–and is very prolific, producing, according to its size, dozens of young which are 10 inches long, very active and snappy.
[Illustration: FIG. 179.–Head of _Lachesis lanceolatus_ after removal of the skin. × 1. _D_, Duct, bent upon itself, from the poison-gland into the tooth; _Dig_, digastric muscle or opener of the jaw; _N_, nostril; _P.G_, poison-gland; _S.Gr_, sensory groove or pit; _S.Q_, point of junction of the squamosal and quadrate; _T.a_, _Temp.a_, anterior, and _T.p_, posterior, temporal muscle.]
_L._ (_Trimeresurus_) _gramineus_ s. _viridis_, to mention one Asiatic species, grows to less than 3 feet in length, is bright green above, sometimes with faint blackish bars; green, yellow, or whitish below, and with a light streak along the outer row of scales. The end of the tail is usually bright red. This beautiful snake has a prehensile tail and is arboreal. Its range extends over the whole of India, to Hong-Kong and to Timor, and even into the Andaman and Nicobar Islands.
_Sistrurus._–With a rattle. The upper surface of the head is covered with nine large shields. A few species in North America east of the Rocky Mountains, e.g. _S. miliarius_.
{648}_Crotalus._–With a rattle. The upper surface of the head is covered with small scales. Range from Southern Canada and British Columbia to Northern Argentina, but not in the West Indian Islands. About ten, mostly closely-allied species.
[Illustration: FIG. 180.–Skull of a Rattle-Snake, _Crotalus durissus_. × 1. A, Lateral view, jaws slightly opened; B, ventral view; C, lateral view, the jaws opened fully in the position of striking; D, dorsal view. Compare this with the diagrammatic figures on p. 588, where the mechanism has been explained. _Col_, Columella auris; _Cond_, condyle; _Cr_ (in B), sphenoidal crest for the attachment of the powerfully developed ventral cranio-cervical muscles; _E.P_, ectopterygoid or transverse bone; _F_, frontal; _Max_, maxillary; _P_, parietal; _P^1_, post-orbital process; _Pal_, palatine; _Pmx_, pre-maxillary; _Pr.f_, prefrontal; _Ptg_, endopterygoid; _Q_, quadrate; _Sq_, squamosal.]
{649}The effect of the poison of Rattle-Snakes has been discussed on p. 589.
_C. horridus_ is the common Rattle-Snake of the United States; _C. confluentus_ is the species in Western and _C. durissus_ the common species in South-Eastern North America. Very large Rattle-Snakes, _C. durissus_, attain a length of 8 feet, others not often more than five. They prey chiefly upon small Mammals, hunting for them at night. In the daytime they are also about, mainly in order to bask. Although they occasionally take to the water in pursuit of their prey, they dislike being wetted by rain, withdrawing then into their holes, appropriating as a rule those of ground-squirrels, rats, and Prairie-dogs. The often-repeated story about Rattle-Snakes living in neighbourly friendship in the holes of Prairie-dogs, together with the little Prairie-owls, is an exaggeration. We do not know how many of the original inmates are eaten. Pairing takes place in the spring. During the cold months they hibernate under ground, often in considerable numbers.
Rattle-Snakes have few enemies besides man and pigs. The latter kill and eat them wherever they can. The rattle is decidedly useful to the snake as an instrument of warning off any approaching possible enemy, since no snake likes to bite unless in self-defence or in order to kill its prey. The noise of the rattle is very loud in dry weather, much duller on clammy days; it is a shrill sound like that of a rattling alarm-clock, and a well-conditioned snake in a room can make conversation well-nigh impossible, and can keep on rattling for half an hour or longer. The rattle is kept in such rapid lateral vibrations that it shows only a blurred image, the rattle standing with its broader sides vertically, not horizontally. They endure captivity for many years, and become tame enough not to hiss and to rattle whenever they are approached.
_C. horridus_ is grey-brown above, usually with a rusty vertebral stripe and with V- or M-shaped blackish cross-bands; the under surface is yellowish; the end of the tail is blackish. The supra-ocular shields are smooth and much narrower than the scaly space between them, and there is only one pair of internasals.
_C. durissus_ s. _adamanteus_ differs from the previous species chiefly by possessing two pairs of internasals; and the dark {650}markings on the body form a handsome pattern of rhombs with lighter centres and yellowish edges. This is the largest species of Rattle-Snake, reaching a length of 8 feet.
_C. confluentus_ has broader, transversely striated, supra-ocular shields. The specific name refers to the continuous series of large brown or red rhomboidal spots on the back.
[Illustration: FIG. 181.–_Crotalus durissus_ s. _adamanteus_ (Rattle-Snake). × ¼.]
_C. terrificus_ ranges from Arizona to Argentina, and is the only species of Rattle-Snake in South America. It differs from the others by having a pair of prefrontal shields behind the pair of internasals.
{651}INDEX
Every reference is to the page: words in italics are names of genera or species; figures in italics indicate that the reference relates to systematic position; figures in thick type refer to an illustration; f. = and in following page or pages; n. = note.
Abdominal armour, of _Cricotus_, 287; of Microsauri, 289; of Prosauri, 290 Abdominal ribs, of Rhynchocephali, 292, 298; of Dinosauria, 414; of _Megalosaurus_, 421 Aberrant scaling of Lacertilia, 495 _Ablepharus_, 560; eyelids, 494 _Acanthodactylus vulgaris_, _559_ _Acanthophis antarcticus_, _635_ Acentrous vertebrae, _i.e._ those without a centrum or body, 4 _Acris_, 186, _189_; _A. gryllus_, _207_ f. Acrochordinae, _606_ _Acrochordus javanicus_, _607_ _Acteosaurus_, _489_ _Actinodon_, _83_, 287, 288 Adams, visit to the Mugger-peer, 455 f. Adaptive characters of Anura, 142 Adhesive apparatus, of tadpoles, 57, 57; of Tree-frogs, 187; of _Thoropa_, 209; of finger-discs of Raninae, 239; of Geckos, 505, 505 _Aelurosaurus_, _307_ Aestivation, of Crocodiles, 457; of Tortoises, 357, 365, 404 _Aetosaurus_, 432; _Ae. ferratus_, _433_, 448 _Agalychnis_, _189_, _206_ _Agama_, _520_; _A. sanguinolenta_, _520_; _A. stellio_, _521_, 521 Agamidae, _513_, _515_ f. _Agamura_, tail, 506 Agassiz, on habits of Alligator Turtle, 341; of _Trionyx_, 407 Age of Chelonia, how to estimate, 326; great age attained by Tortoises, 369, 376, 377; _see also_ Growth, rate of Aglossa, 139, _140_, _143_ f.; distribution, 143 Aglypha, _592_, _606_ f. _Ahaetulla_ s. _Leptophis_, _618_, 619 Aistopodes, _81_ Aldabra, gigantic tortoises of, 373 f., 375 Algae, destructive to shell of tortoises, 357 Allantois, an embryonic outgrowth from the posterior part of the gut,
## acting as a respiratory organ, 278
_Alligator_, _450_, _466_ f.; _A. mississippiensis_, _467_ f.; skull, 468; nesting, 469; _A. sinensis_, 471 Alligator Turtle, 340 _Allopleuron hofmanni_, 380 _Allosaurus_, _422_ Alpine, Newt, _126_; Salamander, _119_ Altitude, high, in which Anura have been found, 181 _Alytes_, _157_ f.; _A. cisternasi_, _160_; _A. obstetricans_, _158_; urino-genital organs, 49 Amblycephalidae, _592_, 593, _637_ _Amblycephalus monticola_, _637_ _Amblyrhynchus_, 528; _A. cristatus_, _533_ _Amblystoma_, skull, 17, 94, 96, _109_, _110_ f., 112; _A. jeffersonianum_, _111_; _A. mavortium_, _115_; _A. opacum_, _110_; _A. persimile_, _111_; _A. punctatum_, _110_; _A. talpoideum_, _110_; _A. tigrinum_, _111_ f.; metamorphosis of, 112 f. Amblystomatinae, _102_, _109_ _Ameiva_, 549 Amnion, a membrane round the embryo, 278 Amphibia, 3 f.; definition, 5; systematic position, 5; numbers of species, 4 Amphicondylous, _i.e._ the occipital part of the skull articulates with the neck by a right and a left knob, 4 _Amphignathodon_, 185; _A. guentheri_, _188_ Amphignathodontinae, _139_, _188_ _Amphisbaena_, _566_; _A. fuliginosa_, _566_ Amphisbaenidae, _514_, _565_ f. _Amphiuma_, 88, 96; _A. means_ s. _tridactyla_, _100_, 101 Amphiumidae, _94_, _97_ {652} _Amphodus_, _210_; _A. wucheri_, 211 Anaconda, 603, 603 _Anaides_ = _Autodax_ (q.v.), _107_ Anal sacs of Chelonia, used as additional respiratory organs, 330 _Anarosaurus pumilio_, _477_ _Anchisaurus_, 415, 417, _421_; skull of _A. coelurus_, 421 _Ancistrodon_, _645_; _A. contortrix_, _646_, 646; _A. halys_, _645_; _A. himalayanus_, _645_; _A. piscivorus_, _645_, 645 Anderson, on nest of _Gavialis_, 452 Andrews, on _Amblystoma_, 110 _Andrias scheuchzeri_, 84 Anelytropidae, _514_, _564_ _Anelytropsis papillosus_, _564_ Anguidae, _513_, _537_ f.; distribution, 501, 529 _Anguis fragilis_, _539_, 539 _Aniella pulchra_, _564_ Aniellidae, _514_, _564_ Annandale, on habits of _Calotes_, 518; of _Liolepis_, 527; of _Rhacophorus_, 247; of _Varanus salvator_, 544 _Anodonta_, as food of _Trionyx_, 407 _Anodontohyla_, _236_ _Anolis_, _528_; _A. carolinensis_, _529_ Anomodontia, _309_ Anura, 7; characters, 138; classification, 139 f., 141; phylogenetic tree of, 142 Anus, asymmetrical position of, 60 Apoda, _84_ f.; affinities, 88; distribution, 89; eyes, 86; skin, 87; skull, 84, 85; spermatozoa, 87; tentacular apparatus, 88; vertebrae, 86; visceral arches, 86 _Archaeopteryx_, 417 _Archegosaurus_, vertebrae, 13, _82_, 287 Arcifera, of Cope, 140; of Boulenger, 140 Arciferous, type of shoulder-girdle, 24, 25 _Arion_, slug, eaten by tortoises, 363 Arrau-turtle (_Podocnemis_), 391 f. Arteria cutanea magna, 144; A. sacralis of Anura, 144 _Arthroleptis_, _241_, _242_; _A. seychellensis_, _243_, 243 _Ascaphus_, _153_ _Asterophrys_, _161_ Athecae, _333_; definition of name, 337 _Atlantosaurus_, 415, _419_; _A. immanis_, _419_, 420 Atlas and Axis, _i.e._ first and second cervical vertebrae; of _Cryptobranchus_, 13; of Crocodilia, 283; of Chelonia, 283, 316; of _Sphenodon_, 283, 294; atlas fused with axis, 307 Atoposauridae, _453_ _Atractaspis_, _638_; dentition, 593 n. Atria, the thin-walled receptive parts (auricles) of the heart Auditory columellar apparatus, of Amphibia, 24; of Anura, 29 Australian, Anura, spawning time and habits of, 201; Lacertilia, 502 _Autodax_, 96, _104_, _107_; _A. lugubris_, _107_; _A. iecanus_, _107_ Autosauri, _491_ f. Axis; _see_ Atlas Axolotl, 65, _112_ f., 112; Neoteny of, 65, 112 _Azemiops feae_, _638_
Balancers of Amphibia, 45 _Baptanodon_, 483, _484_ Barfurth, on absorption of Tadpole's tail, 61 Bartlett, on _Boa constrictor_, 602; on _Pipa_, 152 _Basiliscus_, 528, _530_; _B. americanus_, _530_, 530 Bates, on habits of _Podocnemis_, 392 f. _Batrachomyia_, fly infesting Bufonidae, 177 _Batrachophrynus_, _224_; _B. macrostomus_, 225; _B. brachydactylus_, 224 _Batrachopsis_, _161_ _Batrachoseps_, 96, _104_ _Batrachylodes_, _241_ _Batrachyperus_, 96; _B. sinensis_, _109_ Baur, on _Sphargis_, 336 _Bdellophis_, _90_ Bedriaga, on Axolotl, 114; synopsis of Urodelous Larvae, 59 n. Bell, J., on classification, 8 Bell, Napier, on habits of _Iguana_, 531 _Belodon_, 305, _434_, 448 Bemmelen, on _Sphargis_, 336 Berg, on _Spelerpes fuscus_, 106 Bert, quoted, 571 n. Bidder's organ, 49, 52 Biedermann, on change of colour in _Hyla_, 35 Birds not related to Dinosaurs, 416 f. _Bitis arietans_, _639_, 639; _B. nasicornis_, _640_ Black Snake, of Australia, _634_; of North America, _613_ Blainville, de, on classification, 7 _Blanus cinereus_, _566_ Blood, shape of red corpuscles, 4; temperature, 67 f. Blood-sucker = _Calotes ophiomachus_, 519 Blum, quoted, 642 n. _Boa_, _602_; _B. constrictor_, _602_; _B. dumerili_, _602_; _B. madagascariensis_, _602_ Boettger, on influence of climate and country upon reptiles, 492 f. Boidae, _592_, _596_ f.; skull, 596, 597 Boinae, _601_ f. _Bombinator_, _154_ f., 155; habits, 156 f.; tadpoles, 157; abnormal vertebrae, 22; shoulder-girdle, 25; urino-genital organs, 49; _B. igneus_, _154_, 155; _B. pachypus_, _155_ _Bothrops_, _647_ Boulenger, classification of Amphibia Caudata, 9; {653} on vertebrae of _Pelobates_, 20; on vertebrae of _Bombinator_, 22; number of phalanges in Anura, 27; on poison of Amphibia, 36; on vocal sacs, 48; on modes of fecundation and nursing habits, 54, 56; synopsis of Tadpoles, 59 n.; on tadpoles of _Rana opisthodon_, 260; on classification of Anura, 140, 141; on _Pipa_, 152; on _Scaphiopus solitarius_, 165; on _Alligator sinensis_, 471; on _Lanthanotus_, _542_; on aberrant scaling, 495; on _Heloderma_, 540 n.; on classification of Snakes, 592; on Sea-Snakes, 637; on _Sphargis_, 336 _Boulengerula_, _90_ Box-Tortoises, _362_, 364, 365 Brachial plexus, of Anura, 39 _Brachycephalus_, 226, _227_; _B. ephippium_, _231_ _Brachylophus_, distribution, 501, _528_ Brain, of _Scaphognathus_, 485; small size of, in Dinosaurs, 425 Branchial arches, of Urodela, 16; of Anura, 42 Branchiosauri, _80_ _Branchiosaurus_, skull, 80; _B. salamandroides_, _80_ Brauer, on development of Apoda, 92; on nursing habits of _Arthroleptis_, 243 Breeding of Axolotl, 113 _Breviceps_, shoulder-girdle, 26, 225, 226, _227_, _232_; _B. mossambicus_, _232_ _Brithopus_, _308_ Brongniart, on classification, 7 _Brontosaurus_, 415, _418_; _B. excelsus_, 418 _Brontozoum_, 415, 417; _B. giganteum_, _420_ Brood-pouches, of Anura, 151, 248; of _Hyla goeldii_, 198; of _Nototrema_, 202; of _Rhinoderma_, 228 _Brookesia_, _580_ Brown Adder, _634_ Brown Frog, Common, 251 f., 255 Brücke, quoted, 571 Buchholz, on _Chiromantis_, _244_ f. Budgett, on breeding habits of _Phyllomedusa_, 204; on _Paludicola_, 220; on _Lepidobatrachus_, 218; quick development of _Phryniscus_, 231; on _Bufo marinus_, 179 _Bufo_, sacral vertebra, 22; shoulder-girdle, 26; urine-genital organs, 49; development of adhesive apparatus, 57; _B. agua_, _178_; _B. americanus_, _178_; _B. calamita_, _181_ f.; _B. ceratophrys_, _179_; _B. empusus_ and _B. peltocephalus_, dermal ossifications, 179; _B. jerboa_, 166; _B. lentiginosus_, _178_, _179_; map of distribution, 167, _168_, _169_ f.; _B. marinus_, _178_; _B. mauritanica_ s. _pantherina_, _184_; _B. melanostictus_, _177_, _179_; _B. quercinus_, _178_; _B. variabilis_ = _viridis_, _180_; _B. viridis_, _180_ f., 493; _B. vulgaris_, 170 f., 172; large-sized specimens, 171; immured in buildings, 174; diseases, 176; distribution, 177 Bufonidae, _139_, _166_ f.; distribution, 167; affinities, 166 Bufoniformes, 139 Bullfrog, of America, _Rana catesbiana_, 261; of India, _Callula pulchra_, 234; _Rana tigrina_, 261 _Bungarus coeruleus_ s. _candidus_, _633_; _B. fasciatus_, _633_ Butler, on fat-bodies, 500
_Cabrita_, 551 _Cacopus_, shoulder-girdle, 25, 225, 226, _228_ _Cacosternum_, 225, _227_ _Caiman_, _450_, _471_; vomer, 435; _C. niger_, _471_, _472_; _O. palpebrosus_, _471_; _C. sclerops_, _471_; _C. trigonatus_, _471_, _472_ Calcareous deposits in the skin of Amphibia, 31, 34 _Calliphora silvatica_, fly infesting _Bufo_, 176 _Callophis macclellandi_, _634_ _Calluella_, 235, _236_ _Callula_, 226, _228_, _234_; _C. pulchra_, habits of, _234_ f. _Callulops_, 225, _228_ _Calophrynus_, 225, _227_ _Calotes_, _517_; _C. emma_, _518_; _C. mystaceus_, _519_; _C. ophiomachus_, _519_; _C. versicolor_, _518_ _Calyptocephalus_, 179, _212_, _215_ _Camptosaurus_, _426_ _Capitosaurus_, _83_ Carapace, 321 f., 319, 320, 322, 323; posterior portion movable in _Cinyxis_, _364_, 365; carapace of tortoises, evolution of, 337; composition of, 324 f.; reduction of component elements, 325; reduction in thickness, 373; correlative changes, 328; of _Sphargis_, 335 f.; of _Chelone_, 379; of _Testudo_, 322; of Pleurodira, 389; reduction in Trionychidae, 325; fenestration, 325; with hinge in _Cinyxis_, 364, 365 _Cardioglossa_, _274_ Carettochelydidae, _313_, _314_ _Carettochelys_, 337, 389, 390; _C. insculpta_, _404_; absence of horny shields, 325 Carpet Snake, _598_, 599 Carpus (_see also_ Limbs), of _Eryops_, 286; of _Sphenodon_, 294; of Chelonia, 320, 320; of Eusuchia, 440 _Casarea_, _603_ Case, on _Sphargis_, 336 _Cassina_, _240_ _Causus_, _638_; _C. rhombeatus_, _639_ _Centrolene geckoideum_, _211_ _Cerastes cornutus_, _640_, 641 Ceratobatrachidae, 141 {654} Ceratobatrachinae, _139_, _237_ f. _Ceratobatrachus guentheri_, _237_ _Ceratohyla_, 211 _Ceratophora_, _517_; _C. stoddarti_, _517_; _C. tennenti_, _517_ _Ceratophrys_, _212_, _215_ f.; _C. cornuta_, 216; _C. dorsata_, 215; _C. ornata_, 216, 217 Ceratopsia, _430_ _Ceratosaurus_, 413, 416, 417; _C. nasicornis_, _422_, 422 _Cerberus rhynchops_, _625_ _Cetiosaurus_, _419_ _Chalarodon_, _528_; geographical distribution of; 501 _Chalcides_, _562_; _Ch. bedriagae_, 563; _Ch. guentheri_, 563; _Ch. lineatus_, 563; _Ch. ocellatus_, 563; _Ch. tridactylus_, 563 _Chamaeleon_, _573_; _Ch. bifidus_, 580; _Ch. calcaratus_, 579; _Ch. parsoni_, 580; _Ch. pumilus_, 579, 575; _Ch. vulgaris_, 573, 574, 575 Chamaeleontes, _567_ f.; distribution, 568; skull, 568, 569; tongue, 569 f.; colour-changing mechanism, 570, 571, 573 f.; eggs, 572 Chamaeleontidae, _573_ f. _Chamaerops humilis_, dates of, eaten by _Testudo_, 367 Chameleon, misnamed _Calotes_, _518_; misnamed _Polychrus_, _529_ Chauvin, Marie von, on Axolotl, 113; on _Salamandra atra_, 120 _Chelodina_, suppression of neural plates, 324; intergular shields, 389, 315; skull, 399; _Ch. longicollis_, _402_ f., 403 _Chelone_, skull, 317; skeleton, 320; plastron, 321; shields, 327; intergular shields, 325; _Ch. mydas_, _381_ f.; various modes of fishing, etc., 382, 383; _Ch. imbricata_, _384_, 385 Chelonemydidae, 380 Chelonia, 312; number of species, 312; affinities of, 312; classification, 313; key to living families, 314; plastron, names of the horny shields, 315; 321, 325; vertebrae, 314 f., 316; skull, 280, 317, 356, 364, 379, 400, 405; skeleton of _Testudo_, 319; of _Chelone_, 320; pectoral arch, 318; pelvis, 319; plastron, bones of, 321; limbs, 320; bony shell, 321 f., 322, 323; evolution of, 337; evolution of the horny shields, 326 f., 327; regeneration, 329; sense-organs, 329; digestive apparatus, 330; respiration, 331; growth of _Chrysemys_, 349 Chelonidae, _313_, _314_, _378_ f.; affinities of, 380 Chelydidae, _313_, _314_, _399_; distribution, 332, 333 _Chelydosaurus_, _82_, 287 _Chelydra_, 328; _Ch. serpentina_, _338_ Chelydridae, _313_, _314_, _338_; distribution of, 332 _Chelydropsis_, nuchal plates, 324 _Chelys fimbriata_, _400_; skull, 400, 401; intergular shields, 325 _Chersydrus granulatus_, _607_ _Chioglossa_, 96, _115_; _Ch. lusitanica_, _121_ _Chirixalus_, _241_ _Chiroleptes_, 209, _213_, _221_; _Ch. platycephalus_, _221_ _Chiromantis_, 238, _241_, _244_; _Ch. petersi_, _244_; _Ch. xerampelina_, _244_ _Chirotes_, 564; _Ch. canaliculatus_, _566_ _Chirotherium_, _83_ _Chlamydosaurus kingi_, 522, 523 Choanae, or inner nasal openings, 47 Chorda dorsalis, the axial rod between the gut and the spinal cord, around which the vertebrae are formed, 12 _Chorophilus_, 186, _189_; _Ch. ornatus_, _208_ Chromatophores, 35 _Chrysemys_, costal plates of, 325; green colour of, 328, _346_ f.; colour of iris, 329; _Ch. concinna_, _346_, 349, 350; _Ch. elegans_, _346_; _Ch. picta_, 346, _347_, 348; _Ch. rubriventris_, _346_ _Chthonerpeton_, 87, _90_ _Cimoliasaurus_, _478_; _C. australis_, _478_; _C. cantabrigiensis_, _478_; _C. chilensis_, _478_; _C. haasti_, _478_ Cinosternidae, _313_, _314_, _342_; distribution, 332 _Cinosternum_, 342 f.; arrangement of neural plates, 324; _C. leucostomum_, _342_, 344; _C. odoratum_, _342_, 343; _C. pennsylvanicum_, _342_, 344 _Cinyxis belliana_, _365_; _C. erosa_, _364_, 365; _C. homeana_, _364_ _Cistecephalus_, _310_ _Cistudo_, arrangement of neural plates, 324; _C. Carolina_, 361 f., 364; colour of iris, 329 _Claosaurus_, _429_ Clarke, on habits and development of _Alligator_, 467 Classification of Amphibia, historical account, 7 f. Clawed Toad (_Xenopus_), _146_ f. Claws or nails of Amphibia, 32 Cleithra = the pair of additional clavicles; of Stegocephali, 79; of _Pareiasaurus_, 304, 305 _Clemmys_, _356_ f.; _C. caspica_, _358_; _C. insculpta_, _359_; _C. leprosa_, _356_ f., 353; skull, 356 _Clepsydrops_, _308_ _Clidastes tortor_, _490_ Cloaca, of Chelonia, 330; of Crocodiles, 445; of Lacertilia, 498 _Cnemidophorus_, _549_; _C. sexlineatus_, _549_ Cobra, _627_, 627 Coccyx, _s._ Os coccygeum, of Anura, 20, 21, 22 {655} _Coecilia_, _89_ Coeciliidae, _89_ f.; distribution of, 89 _Coelopeltis_, _624_; _C. monspessulana_ s. _lacertina_, _624_ _Coelurus_, _415_; _C. gracilis_, _423_ Colombo, gigantic tortoise of, 377 Coloration, warning colours of Amphibia, 38, 156; protective, of Amphibia, 191, 238, 252; of deserticolous reptiles, 494 _Colosthetus_, 238, _242_ Colour, changes of, in Anura, 35; in _Calotes_, 518, 519, 520; in Geckos, 509; in Lacertilia, 498; mechanism of changing, in Chameleons, 570, 571 _Coluber_, _615_ f.; _C. aesculapii_ = _flavescens_ = _longissimus_, _616_ f.; _C. leopardinus_, _616_; _C. (Rhinechis) scalaris_, _617_ Colubridae, _593_, _606_ f. Colubrinae, _607_ f. Columella cranii, 496, 550, 551 Columellar auditory chain, of Amphibia, 4; of Anura, 29; of Crocodiles, 446; of Lizards, 496 Comoro Islands, Tortoises of, 373 _Compsognathus_, _415_, 416, 417; _C. longipes_, _423_, 425 Condyle, occipital, of Theromorpha, 302; exaggerated importance of its character, 285 _Conolophus subcristatus_, _532_ Conus arteriosus, continuation of the heart beyond the ventricles so far as it contains valves, 6 Cope, on classification of Amphibia, 9; of Anura, 140, 141; on _Siren_, 136; on hand-skeleton of _Eryops_, 286; on _Sphargis_, 336; classification of Lacertae, 513; classification of Snakes, 592 _Cophophryne_, 167, _168_ _Cophyla_, _236_ Copper-head, _646_, 646 Copulatory organs, of Lacertilia, 499; absent in _Sphenodon_, 294; of Chelonia, 330; of Snakes, 585 Coqui, 214 _Coronella_, _619_; _C. austriaca_ s. _laevis_, _619_, 620; _C. girondica_, _621_ _Cornufer_, _241_, _243_; _C. corrugatus_, _244_; _C. johnstoni_, _243_; _C. solomonis_, _244_; _C. unicolor_, _244_ _Corythomantis_, _189_, _207_; _C. greeningi_, 207 Costal plates of Chelonia, 324 f., 322, 323 _Craspedocephalus_, 647 Crested Newt, 125, 125 _Cricotus_, 285, _285_; _C. heteroclitus_, 287 _Crinia_, _213_; spawning, 223 Crocodilia, _431_ f.; skeleton, 434 f.; skull, 280, 434 f.; atlas and axis, 283, 431, 439; affinities, 432; teeth, 437; skin, 442; dermal armour, 442; skin glands, 443; tongue, 443; respiratory organs, 444; "diaphragm," 444; digestive organs, 444; cloaca, 445; heart, 445; ear, 445; eye, 446; geographical distribution, 446, 446; voice, 447; habits, 447; propagation, 447; classification, 448 Crocodilidae, _454_ _Crocodilus_, _450_, _454_ f.; teeth, 437; skin glands, 443; _C. acutus_, _446_, 449; _C. americanus_, _466_; skull, 466; _C. biporcatus_ = _porosus_, _458_; rate of growth, 459; _C. cataphractus_, _465_; _C. intermedius_, _466_; _C. johnstoni_, _466_; _C. niloticus_ = _vulgaris_, _460_ f., 449, 461; habits, 462 f.; _C. palustris_, 449, _454_; skull, 455; _C. porosus_, _458_; skull, 458; _C. vulgaris_, 449, _460_ f. Crotalinae, _644_ _Crotalus_, _648_; rattle of, 644; _C. adamanteus_, _649_, 650; _C. confluentus_, 649, _650_; _C. durissus_, 648, _649_, 650; _C. horridus_, _649_; _C. terrificus_, _650_ _Cryptobranchus_, 84, _96_, _99_; fossil, 84; _C. alleghaniensis_, _97_; _C. japonicus_, 98, 99 _Cryptoclidus_, shoulder-girdle, 474, 475, _478_ Cryptodira, _313_, _338_ _Cryptopsophis_, _89_; _C. multiplicatus_, _92_ _Cryptotis_, _213_ Cutis, of Amphibia, 33 f. _Cyamodus_, _311_ _Cyclanorbis_, _411_; nuchal plate, 324 _Cycloderma_, _411_ _Cyclodus_ s. _Tiliqua_, _561_; _C. gigas_, _561_, 562 _Cyclorhamphus_, _212_ _Cynognathus_, 301, 302, 303; _C. berryi_, _307_; _C. crateronotus_, _306_; _C. platyceps_, _307_ Cystignathidae, _139_, _209_ f.; distribution, 161 Cystignathinae, _139_, _211_ f. _Cystignathus_ = _Leptodactylus_, 210, _218_
Dab = _Uromastix_, _526_, 526 _Daboia_, _643_ _Dactylethra_; see _Xenopus_, _146_ f. Darwin, on _Conolophus_, 532 n.; on tortoises of Galapagos Islands, 377 _Dasypeltis scabra_, _622_, 622; dentition, 593 n. Davison, on breeding of _Amphiuma_, 101 _Dawsonia_, _289_ Death Adder, _635_ Denburgh, van, on _Autodax_, 107 _Dendrobates_, _272_; _D. braccatus_, _273_; _D. tinctorius_, _272_, 273; _D. trivittatus_, _273_; _D. typographus_, _273_; various uses of its poison, 38 Dendrobatinae, _139_, _237_, _272_ f.; {656} distribution, 239 _Dendrophis_, _618_; _D. punctulatus_, _618_, 618 Dendrophryniscinae, _139_, _224_ _Dendrophryniscus brevipollicatus_, _224_ Dentition, of snakes, 582, 592, 593; _see_ also Teeth Dermal armour, of _Cricotus_, 287; of Microsauri, 289; of Prosauri, 290; of Theromorpha, 302; of Chelonia, 321 f., 337; of Dinosauria, 415; of Pseudosuchia, 433; of Parasuchia, 434; of Crocodiles, 442 Dermal ossification in Anura, 179, 190, 210 Dermatemydidae, _313_, _314_, _341_; distribution of, 332 _Dermatemys mawi_, _341_, 342 _Dermatochelys coriacea_, _333_ f., 334 _Dermophis_, _89_, _93_; _D. thomensis_, _93_ Deserticolous reptiles, 493 f. Desmognathinae, _102_ _Desmognathus_, 96, _102_; _D. fuscus_, _102_, 103 _Deuterosaurus_, _308_ Development, of Anura, 56 f., 57; of horny teeth, 58; of Apoda, 92; of _Crocodilus_, 465; of _Alligator_, 467 _Diadectes_, _308_ _Diademodon_, _309_ _Diaglena_, 185, _189_; _D. jordani_, _207_; _D. petasata_, _207_ Diaphragm, of Anura, 144; of crocodiles, 444 Diapophyses (the lateral or "transverse" processes of the neural arches) of Anura, 138, 141 Dibamidae, _514_, _564_ _Dibamus novae-guineae_, _564_ _Dicamptodon_, 96; _D. ensatus_, _109_ _Diclonius_ = _Hadrosaurus_, _429_ _Dicynodon_, 301, 302, 303, _310_; skull, 280; _D. leoniceps_, _310_; _D. orientalis_, _310_; _D. tigriceps_, _310_ Digestive apparatus, of Chelonia, 330; of crocodiles, 444; of Lacertilia, 498 Digits = Fingers and Toes. Number of digits in Urodela, 15, 16; in Anura, 26; terminal phalanges, 26; number of joints, 27; adhesive discs, 27; variability in numbers, 563; digits of _Eryops_, 286; of Crocodiles, 441; of Plesiosauri, 475; of Geckos, 505 _Dimetrodon_, _308_ _Dimorphodon macronyx_, _486_ Dinosauria, _412_; affinities of, 415; analogies with Birds, 416 _Diplocynodon_, 448; _D. hastingsiae_, _454_ _Diplodocus longus_, _419_ f.; skull, 419 _Diplovertebron_, _287_, 288 Dipsadomorphinae, _623_ f. _Dipsadomorphus_, _623_; _D. cyaneus_, _624_; _D. trigonatus_, _623_ _Dipsas bucephala_, _624_ Discoglossidae, _139_, _152_ f. _Discoglossus_, urino-genital organs, 49, _153_; _D. pictus_, 153 f. _Dissorophus multicinctus_, _82_ _Distira cyanocincta_, _637_; _D. semperi_, _636_ Distribution, geographical; _see_ Maps Dolichosauri, _489_ _Dolichosaurus longicollis_, _489_ _Dolichosoma longissimum_, _81_ _Doliophis intestinalis_, _634_ Dollo, on _Sphargis_, 336 _Dracaena_, _547_; _D. guianensis_, _549_ _Draco_, _516_; _D. dussumieri_, _516_; _D. volans_, _516_, 516 Duméril, 7, 139; and Bibron, on classification of Snakes, 592 Dwarf Chameleon, _579_ Dyscophinae, _139_, _235_ f. _Dyscophus_, _236_; _D. antongili_, _236_
Ear, of Chelonia, 330; of Crocodiles, 445 f.; of Snakes, 583 Ear-opening of deserticolous reptiles, 494 _Echeneis remora_, used for turtle fishing, 382 _Echidna_ s. _Bitis_, _639_, 639 _Echis_, _640_; _E. arenicola_, deserticolous, 493 _Edalorhina_, _212_ Eggs of Amphibia, 53; mode of deposition in Amphibia, 54-56; of _Ichthyophis_, 91; and spermatophore of _Triton viridescens_, 128; nursing and taking care of, 55; by _Pipa_, 151; by _Alytes_, 159; by _Rhacophorus reticulatus_, 248; by _Nototrema_, 188, _202_; by _Amphignathodon_, _188_; by _Hyla goeldii_, 198, 198; by _Leptodactylus mystacinus_, 219; by _Rhinoderma_, _228_; by _Rhacophorus_, _248_; by _Desmognathus fuscus_, 103, 103; number of: in _Bufo vulgaris_, 175; in _Bufo viridis_, 181; in _Hyla arborea_, 193; in _Rana esculenta_, 270 Eggs of Reptilia: _Sphenodon_, 299; Chelonia, 331; _Testudo graeca_, 369; _T. ibera_, 369; _T. elegans_, 371; _T. polyphemus_, 372; _Emys orbicularis_, 355; _Clemmys leprosa_, 358; _Chelone mydas_, 382; _Thalassochelys caretta_, 387; _Podocnemis expansa_, 393 f., 398; _Trionyx_, 408; mode of laying by _Emys_, 355; by _Podocnemis_, 393; used commercially, 394 f.; enormous destruction of, 395, 399; _Crocodilus_, 463, 464 f.; _Alligator_, 470; eggs and nest of _Gavialis_, 452; Lacertilia, 499; increasing in size after deposition, 499; Geckos, 506, 508, 509, 511; _Tarentola_, 509; _Lacerta viridis_, 555; _Chameleons_, 572 Egg-sac, of _Salamandrella_, 110 {657} Egg-tooth, of Lacertilia, 499 Eimer, on habits of _Lacerta_, 552; on _L. coerulea_, 558 _Elachistodon westermanni_, _625_ Elachistodontinae, _625_ _Elaphis_ s. _Coluber_, _615_ f. Elapinae, _626_ _Elaps corallinus_, _635_ Elasmosauridae, _478_ _Elasmosaurus_, _478_ _Elginia_, 301, 304; _E. mirabilis_, skull, 280, _305_ _Elosia_, _212_ _Elseya_, 389, 399 Emerald Lizard, _555_ Emery, on hand-skeleton of _Eryops_, 286 _Empedias molaris_, _308_ _Emyda_, _411_ _Emydura_, 389, 399 _Emys_, _350_ f.; _E. blandingi_, _355_; _E. europaea_ = _orbicularis_, _351_ f., 353 Enaliosauri, _476_ _Endothiodon_, _307_ _Engystoma_, _227_, _231_; _E. carolinense_, _232_ Engystomatidae, _139_, _225_ f. Engystomatinae, _139_, _225_ f. _Engystomops_, 166, _168_ _Enhydrina valakadien_ s. _bengalensis_, _636_, 636 _Enygrus_, _601_ _Eosphargis_, 336, 337 Epichordal type of vertebrae, 20, 145 Epidermis, of Amphibia, 31 f.; sense-organs in, 33 _Equisetum_, eaten by _Uromastix_, 525 _Eremias_, 551; deserticolous, 493 _Erpetosuchus_, _433_ _Eryops_, 285, _286_; trunk-vertebrae, 286, 288, 304; _E. megacephalus_, 286 _Eryx_, _604_; _E. jaculus_, _604_; deserticolous, 493 Escuerzo = _Ceratophrys_, 216 Espada, on _Rhinoderma_, 228 Eublepharinae, _512_ _Euchirosaurus_, _83_, 287 _Eunectes murinus_, 603, 603 _Euprepes vittata_, _562_ _Euproctus_ = _Triton_, _130_ _Eurysternum_, 380 Eustachian tubes, of Anura, 29; of Pelobatidae, 161; of Aglossa, 143 _Eusuchia_, _434_ Eye, of Apoda, 86; of Chelonia, 329; of deserticolous reptiles, 494; of Chameleons, 569; of Snakes, 583 Eyed Lizard, _556_, 556 Eyelid, of Geckos, 504, 512; transparent in _Chelodina_, 329; lower, transparent in Lacertidae, 551; in Scincidae, 560
Fasting, of _Chrysemys_, 347 Fat-bodies, of Amphibia, 49, 52; of Lacertilia, 500 Fecundation, various modes of, in Amphibia, 54; in Apoda, 87 Fer-de-Lance, _647_ Ferreiro = _Hyla faber_, _196_ f. _Feylinia_, _564_ Fingers, number of, in Urodela, 15; number of joints in Anura, 26, 27; terminal modifications of, in Anura, 26; mechanism of adhesive discs in Hylidae, 187 Fire Salamander, _115_ Firmisternal shoulder-girdle, 24, 25 Firmisternia, 140 Fischer-Sigwart, on growth of _Alytes_, 159 f.; on growth of _Bufo_, 175; on gestation of _Chalcides_, 563 Fletcher, on spawning of Australian frogs, 201, 223 Flower, S. S., on habits of _Rhacophorus_, 249; _Phrynella pollicaris_, 233; _Callula pulchra_, 234 Flying Dragon, _516_ Flying Frog, _Rhacophorus_, 245 f., 246 Foot, tridactyle, in _Hallopus_, 423; bird-like in _Compsognathus_, 423 Fore-limb, of Urodela, 15; of Anura, 26; of Proreptilia, 286; of Microsauri, 289; of Prosauri, 290, 298; of Theromorpha, 302; of Chelonia, 320; of Dinosauria, 414, 423, 425, 427; of Crocodilia, 440; of Plesiosauria, 475; of Ichthyosauria, 481; of Pterosauria, 485; of Pythonomorpha, 489; of Lacertilia, 497 Frog, _see_ Rana. Grassfrog, 251; Water-frog, 263, 268, 269
Gage, on _Triton viridescens_, 129 Galapagos Islands, tortoises of, 372, 377 f. _Galesaurus_, _307_ _Gampsosteonyx_, _271_; _G. batesi_, _238_, _240_ Gasco, on spawning of newts, 124 Gastrechmia, 140, 141, _232_ Gastrocentrous vertebrae, defined, 282 Gaupp, on frogs' respiration, 47 n. Gavialidae, _451_ f. _Gavialis_, 435, 436, _451_; _G. gangeticus_, _452_; skull, 449, 452 _Gavialosuchus_, _453_ _Gecko_, _511_; _G. stentor_, _511_; _G. verus_ = _guttatus_ = _verticillatus_, _511_ _Geckolepis_, deserticolous, 493 Geckones, _502_ f.; distribution, 500, 503; adhesive apparatus, 505, 505; voice, 506; reproduction of tail, 506; eyelids, 504, 512 Geckonidae, _507_ f. Geckoninae, _507_ f. Gegenbaur, on classification, 9 _Gegenophis_, 87, _90 Geikia_, _310_ {658} Genital organs, of Amphibia, 48 f., 49 _Genyophryne_, _236_; _G. thomsoni_, _236_ Genyophrynidae, 141 Genyophryninae, _139_, _236_ Geographical distribution, principles of, 69 f.; regions and sub-regions, 74 f. (for details _see also_ Maps); of Apoda, 89; of Urodela, 95, 96; of Anura, 143, 161, 167, 185, 239; of Chelonia, 331 f., 332, 333; of Crocodilia, 446; of Lacertilia, 500 f., 515, 529, 543, 552, 565, 568; of Snakes, 585 _Geomolge_, 96 _Geosaurus_, _451_ _Geotriton_, 97 _Geotrypetes_, _89_ _Gerrhonotus_, _538_; _G. coeruleus_, _538_ Gerrhosauridae, _514_, _559_ _Gerrhosaurus flavigularis_, _559_ Gharial, _452_; _see_ also _Gavialis_ Gigantic Tortoises, _372_ f. Gila Monster, _541_ Gills, definition, 40; development of, 41, 43; retention of, 40; external and internal, 43 f.; operculum of, 44; of _Nototrema_, 203 Gill-clefts, 42; of Urodela, 42; of Anura, 42 Girtanner, on musical appreciation of tortoises, 368 Glass-Snake, _538_ _Glauconia_, _594_ Glauconiidae, _592_, _594_ _Glyphoglossus_, 225, 226, _228_, _233_; _G. molossus_, _233_ Goeldi, on _Hyla faber_, 197; on habits of _Podocnemis expansa_, 397 f. _Gomphognathus_, _308_, 309 _Gondwanosaurus_, _83_ _Gongylus_, _562_ Goniopholidae, _453_ _Goniopholis_, 448, _453_; _G. crassidens_, _453_; _G. simus_, 453 _Gordonia_, 301, 303, _310_; skull, 280 Grass-Frog, 251 f., 255 Grass-Snake, _608_ f. Greek Tortoise, _365_ f. Green Lizard, _555_ Green Toad, _180_ Green, or Edible, Turtle, _381_ f. Groenberg, on _Pipa_, 149 Growth, rate of, in _Testudo ibera_, 370; _Chrysemys picta_, 349; _Emys orbicularis_, 351, 355 Gular shields of Chelonia, 315 Gundlach, on _Leptodactylus_, 219 Günther, 140; on gigantic Tortoises, 374; on classification of Snakes, 592 Gutzeit, on horny teeth of Tadpoles, 58 _Gymnodactylus_, tail, 506, _512_, 512; deserticolous, 493 Gymnophiona, _84_ f. _Gymnophis_, _90_ _Gymnophthalmus_, aberrant scaling, 495
Haast, on habits of _Sphenodon_, 299 _Hadrosaurus mirabilis_, _429_ Haeckel, on classification, 9 _Hallopus victor_, _423_ Hamadryad, _632_ Hand-skeleton, excalation of second finger in _Eryops_, 286 _Haptoglossa_, 96 Hardun = _Agama stellio_, _521_ _Hatteria_–see _Sphenodon_, 293 f. Hawksbill-Turtle, _384_ f. Hay, on _Sphargis_, 337 Hearing of Chelonia, 330 Heart, modification of, in lungless Amphibia, 47 Hedonic glands (ἡδονή, lust), 443 _Heleioporus_, _213_, _222_; _H. albopunctatus_, _222_; _H. pictus_, _222_ _Helix virgata_, eaten by _Hyla coerulea_, 200 _Heloderma horridum_, _540_; _H. suspectum_, _540_, 541 Helodermatidae, _513_, _540_ f. _Hemidactylus turcicus_, _508_, 508 Hemiphractinae, _139_, _210_ f. _Hemiphractus_, _210_ _Hemisus_, 225, 226, _228_, _232_; shoulder-girdle, 25; _H. guttatum_, _232_; _H. sudanense_, _232_ Hensel, on _Bufo marinus_, 179; on tadpoles of _Thoropa_, 209; on nest-building of _Leptodactylus_, 219 Herodotus, on Crocodiles, 462 _Herpele_, _90_ _Herpestes griseus_ (Mongoos), 629 Hibernation, temperature of blood during, 68; of Tortoises, 347, 349, 354, 358, 360, 363, 365, 369, 376; of Crocodiles, 447 Hinckley, on tadpoles of _Hyla versicolor_, 195 Hind-limbs, of Urodela, 15; of Anura, 27; of Prosauria, 289; of Theromorpha, 302, 305; of Chelonia, 321; of Dinosauria, 414, 423, 425, 427, 429; of Crocodilia, 440; of Plesiosauria, 476; of Ichthyosauria, 480; of Pterosauria, 486; of Lacertilia, 497; of Ophidia, 593, 594, 596 _Hipistes hydrinus_, _625_ Holbrook, on the Black Snake, _613_; on habits of _Alligator_, 470 f. Holoblastic eggs; the whole mass of the egg undergoes the process of cleavage, 53 Homalopsinae, _625_ _Homalopsis buccata_, _625_ Homing of turtles, instances of, 386 _Homoeosaurus pulchellus_, _292_ {659} _Homopholis_, deserticolous, 493 Homothermous, defined, 68 _Hoplocephalus curtus_, _634_ _Hoplurus_, _528_; geographical distribution, 501 Horned Toad = _Ceratophrys_, 215 f., 216, 217 Horned Viper, _640_, 641 Horny nail, on tail of Chelonia, 328 Horny scales, of Chelonia, 328 Horny shields, of Chelonia, 314, 315, 322, 323, 326 f., 327; their growth, 326 Horny teeth, of Anura, 58 Hose, on reproduction of tortoise-shell, 386 Howes, on development of _Sphenodon_, 298 Humerus of _Sphenodon_, 294 Hutton, on Starred Tortoise, 370 f. Huxley, on classification, 9 _Hydraspis_, 389; skull, 399 _Hydromedusa_, 389, _404_; _H. tectifera_, _404_ Hydrophinae, _635_ _Hydrophis obscura_, _636_, 636 _Hydrosaurus_, _543_ _Hyla_, _189_ f.; _H. arborea_, _190_ f., 190; var. _meridionalis_, _191_; var. _savignyi_ = _japonica_, 191; _H. aurea_, _201_ f.; spawning, 201; _H. carolinensis_ s. _lateralis_, _194_; _H. coerulea_, _198_ f., 199; spawning, 223; _H. dasynotus_ and _H. nigromaculata_, dermal ossifications of, 190; _H. ewingi_, _201_; spawning, 223; _H. faber_, peculiar nursing habits, 196 f.; _H. femoralis_, _194_; _H. goeldii_, _198_, 198; female with eggs, 198; _H. maxima_, _196_; _H. nebulosa_ s. _luteola_, _197_; nest-building, 198; _H. polytaenia_, _198_; _H. squirella_, _194_; _H. vasta_, _195_; _H. versicolor_, _194_ f. Hylaeformes, 139 _Hylaeobatrachus croyi_, _83_ _Hylaeosaurus_, _425_ _Hylambates_, 238, _240_ _Hylella_, 186, _189_, _203_ Hylidae, _139_, _185_ f.; distribution, 185, 186; mechanism of climbing, 187; map of distribution, 185; distribution, 186 Hylinae, _139_, _189_ f. _Hylixalus_, 238, _242_ _Hylodes_, _212_; _H. martinicensis_, _214_ f., 214; _H. abbreviatus_ = _Thoropa miliaris_, 209 _Hylonomus_, 288, _289_ _Hyloplesion longicostatum_, _289_ _Hylopsis_, _212_; _H. platycephalus_, _224_ _Hylorhina_, _212_ _Hymenochirus_, 143, 144, _149_ _Hynobius_, 96, _109_ Hyoid apparatus, of Urodela, 16; of Anura, 31; of Chelonia, 318; of _Chelys_, 400; of Lacertilia, 496 _Hyperodapedon gordoni_, _292_ _Hyperolia_, _213_; spawning, 223 Hyperphalangeal limbs, of Eusuchia, 441; of Ichthyosauri, 480 _Hypogeophis_, 87, _89_, _92_; _H. alternans_, _92_; _H. rostratus_, _92_ _Hypopachus_, 226, _227_, 235 _Hypsilophodon foxi_, _427_ _Hypsirhina plumbea_, _625_
Iberian Water-tortoise, 357 f. Ichthyodea, distribution of, 95 _Ichthyophis_, skull, 85, 88, _89_ f., 91; _I. glutinosa_, _90_, 91; _I. monochrous_, _90_ Ichthyopsida, 5, 277 Ichthyopterygia, 476 Ichthyosauri, _483_ f. Ichthyosauria, _478_ f.; skull, 281, 479; vertebrae, 480; limbs, 481; shoulder-girdle, 481 _Ichthyosaurus_, _483_; _I. communis_, _483_; _I. campylodon_, _483_; _I. quadriscissus_, 483; _I. tenuirostris_, _483_; _I. trigonodon_, _483_ _Idiochelys_, 380 _Iguana_, 306, 528, _531_; _I. tuberculata_, _531_ Iguanidae, _513_, _528_ f.; distribution, 501, 529 _Iguanodon_, 416, 417, _427_; _I. bernissartensis_, _428_, 428; _I. mantelli_, _427_ Ihering, on breeding habits of _Phyllomedusa_, 205 f., 206 Ikeda, on nursing habits of _Rhacophorus_, 248 _Ilysia_, _595_ Ilysiidae, _592_, _594_ Inframarginal shields, 326, 315 Intergular shields of Chelonia, 325, 315 Iris, colour of, in Chelonia, 329 _Ixalus_, 238, _241_
Jaw, lower, of _Salamandra_, 17; of Urodela, 18; of Anura, 30
Keller, quoted, 571 n. _Keraterpeton_, _81_, 288; _K. crassum_, _81_ Kidneys of Amphibia, 48 f., 49 Klinckowstroem, on _Pipa_, 149 Kollmann, on Neoteny, 64 Krait, _633_
Labial glands of _Heloderma_, 498 _Labyrinthodon_, _83_ Labyrinthodonta, _82_ _Lacerta_, _553_; _L. agilis_, _554_; _L. muralis_, _557_; _L. ocellata_, _556_ f., 556; _L. pater_, _556_; _L. schreiberi_, _555_; _L. tangitana_, _556_; _L. viridis_, _555_; skull, 550; _L. vivipara_, _553_ Lacertae, _513_ f. Lacertidae, _514_, _549_ f.; skull, 550; distribution, 552 Lacertilia, 491 f.; {660} skeleton, 494 f.; skin, 497; change of colour, 498 _Lachesis gramineus_, _647_; _L. lanceolatus_, _646_, 647 Land-tortoises, _364_ f. Lanthanotidae, _514_, _541_ f. _Lanthanotus borneensis_, _541_ _Laosaurus_, _427_ _Lariosaurus_, 473, 474; _L. balsami_, _477_ Larvae, of _Ichthyophis_, 91; of _Hypogeophis_, 92; of _Amblystoma_, 112; of _Triton waltli_, 131 Latreille, on classification, 7, 8 Laurenti, on classification, 7 Leathery Turtle = _Sphargis_, 333 f., 334 Lechriodonta, distribution of, 95; defined, 102 _Lepidobatrachus_, _212_, _218_ _Lepidophyma_, _547_ Lepospondylous, defined, 79 _Leptobrachium_, _161_; _L. carinense_, _166_ _Leptodactylus_, _212_, 218 f.; _L. albilabris_, 219; _L. mystacinus_, 219; _L. ocellatus_, 219; _L. typhonius_, 219 f. _Leptognathus_, _624_ _Leptophis_, _618_; _L. liocerus_, _618_, 619 Leslie, on _Xenopus_, 146 Leuckart, on classification, 8 Leydig's duct, defined, 48, 49 _Lialis burtoni_, _567_ Limbs, of Amphibia, 26, 27; Stegocephali, 79, 83; _Eryops_, 286; Microsauri, 289; Prosauri, 291; _Sphenodon_, 298; Theromorpha, 302; Pareiasauri, 305; Chelonia, 320, 319, 320; _Sphargis_, 335; Chelonidae, 379; Dinosauria, 414 f., 418, 420; _Compsognathus_, 423; Stegosauri, 426 f.; _Iguanodon_, 428, 428; Eusuchia, 440; Plesiosauria, 475, 475; _Lariosaurus_, 477; Ichthyosauria, 480; Pterosauria, 485, 485; Lacertilia, 495; Geckones, 505; Chameleons, 568; reduction of, in Lacertilia, 497; in Ophidia, 593, 594, 596 _Limnodynastes_, _213_, 222; spawning, 223 _Limnomedusa_, _212_ Linnaeus, on classification, 7 _Liodon haumuriensis_, _490_ _Liolepis belli_, _527_ _Liopelma_, 153; _L. hochstetteri_, _160_ _Liophryne_, 225, _227_ _Liosaurus_, _529_ Lissamphibia, _84_ f. Lizard, Common English, _553_; Emerald, _555_; Eyed, _556_, 556; Green, _555_; Sand, _554_; Wall, _557_ Lizards, _491_ f. Locality, sense of, in Tortoises, 368, 387 Loggerhead Turtle, _387_; individual varieties of shields, 327, 388 Longevity, of _Testudo daudini_, 376; _T. graeca_, 369; _T. ibera_, 369; _T. sumeirei_, 377 _Loxocemus bicolor_, _598_ _Loxomma_, _83_ _Lucilia bufonivora_, fly infesting _Bufo_, 176 Lungs, definition, 40; suppression of, 46; of Aglossa, 144; of Lacertilia, 499 Luth, or Leathery Turtle, 333 f., 334 _Lycosaurus_, _307_ _Lygosoma_, distribution, 501 Lymph-spaces, in the cutis of Anura, 34 _Lyriocephalus scutatus_, 517, 518 _Lytoloma_, 336, 380
_Mabuia_, _562_; distribution, 501; eyelids, 494; _M. vittata_, _562_ _Macroclemmys_, 326; _M. temmincki_, _340_ f., 340 _Macroprotodon cucullatus_, _624_ Macrorhynchidae, _451_ Madagascar, Lacertilia of, 502 _Malacoclemmys terrapin_, _359_ f.; commercial breeding-farms, 360 Malpighian, body, 49; stratum, 32 Mammalian affinities of Theromorpha, 303, 309 _Manculus_, 96, _103_, _106_; _M. quadridigitatus_, _106_ Mandible, composition of, in Crocodiles, 437; very Mammalian in _Gomphognathus_, 309 _Mantella_, 274 _Mantophryne_, 225, _227_ Maps showing geographical distribution, of Coeciliidae, 89; Urodela, 95; Aglossa, 143; Cystignathidae, Discoglossidae, Pelobatidae, 161; Bufonidae, 167; Hylidae, 185; Ranidae, 239; Chelydidae, 332, 333; Chelydridae, 332; Cinosternidae, 332; Dermatemydidae, 332; Pelomedusidae, 332; Platysternidae, 332; Trionychidae, 333; Crocodilia, 446; Geckonidae, 503; Agamidae, 515; Anguidae, 529; Iguanidae, 529; Zonuridae, 529; Varanidae, 543; Lacertidae, 552; Amphisbaenidae, 565; Chamaeleontes, 568; Snakes, dangerously poisonous, 585; Elapinae, 626; Crotalinae, 644; Viperinae, 638 Marbled Newt, _126_ Marginal plates of Chelonia, 325, 322, 323 Marginal shields, 326 Marsh, on Axolotl, 115 Marsh Crocodile, _455_ Marshall, on distribution of Uropeltidae, 595 Mascarene Islands, tortoises of, 373 f. Mason, on habits of _Calotes_, 519; on Python legends, 599; on _Varanus_, 544 _Mastodonsaurus_, _83_ Matamata = _Chelys fimbriata_, _400_, 401 Mauritius, gigantic tortoises, 373 f., 376 Mecodonta, distribution of, 95; {661} defined, 102 _Megalixalus_, 238, _240_ _Megalophrys_, _161_; tadpole, 60 _Megalosaurus_, 416; _M. bucklandi_, _421_ _Megalotriton_, _83_ _Melanerpeton_, _81_, _289_ _Melanobatrachus_, 226, _228_ _Melosaurus_, 287 _Menobranchus lateralis_, _132_ _Menopoma_, _97_ Mento-Meckelian cartilages, 30 Meroblastic eggs; part of the egg only undergoes the process of cleavage, 53 Merrem, on classification, 8 Mesosauridae, _476_ _Mesosaurus_, _476_; _M. tenuidens_, _476_ Metamorphosis of Tadpoles, 56 f. Metasternum of Anura, 26, 25; taxonomic value, 141; definition, 26 Metatarsalia of Theropoda, 420 _Metopias_, _83_ _Metopoceros cornutus_, _532_ _Metriorhynchidae_, _451_ _Metriorhynchus_, atlas and axis, 283, 431, _451_ Metzdorff, on Axolotl, 113 _Micrixalus_, _241_ _Microgomphodon_, _308_, 309 _Microhyla_, _228_ Microsauri, _288_ Midwife-toad, 158 _Mimosa_ (plant), 629 _Miolania_, 390 _Mixophyes_, _213_; spawning, 213 _Mixosaurus_, limbs, 480, 481, _483_ _Molge_–see _Triton_, _122_ _Moloch horridus_, _527_, 527 Mongoos and Cobra, 629 Monitor, _543_ _Morosaurus grandis_, _419_; pelvis, 419 Mosasauri, _489_ f. _Mosasaurus_, _489_; _M. camperi_, _490_ Moult of Geckos, 510; of Chameleons, 571; of Snakes, 583 Mud-diver, _165_ Mud-turtle, 342 Mugger, _454_ Müller, J., on classification, 8 Müllerian duct, 49, 51 Musical appreciation of Tortoises, 368 _Myobatrachus_, 166, 167, _168_; _M. gouldi_, _184_, 227, _236_ _Mystriosaurus_, 432, _451_
Nails or claws of Amphibia, 32 _Naja_, _626_; _N. bungarus_ s. _elaps_, _632_; _N. haje_, 628, _632_; _N. tripudians_, _627_, 627 _Nannobatrachus_, 238, _240_ _Naosaurus claviger_, _308_ Natterjack, _181_ _Naultinus elegans_, 506 Neck, mode of withdrawing in Chelonia, 328 f. _Nectes_, 166, _168_; _N. subasper_, _169_ _Nectophryne_, 166, _168_; _N. afra_, _169_; _N. tuberculosa_, _169_; _N. guentheri_, _169_; _N. hosei_, _169_; _N. misera_, _169_ _Necturus_, pelvis, 15, 96, _132_; _N. maculatus_, _132_ Neoteny, 63 f.; defined, 64 Nephrostomes, 48, 49 _Nephrurus asper_, tail, 506 Nerves, spinal, of Amphibia, 38; cranial, 39 Nest, of _Crocodilus_, 463; of _Gavialis_, 452 Neural plates, of Chelonia, 323 f., 322, 323; suppression of plates, 324; in Pleurodira, 389; of _Dermatemys_, 342 _Neusticosaurus_, _477_ Newt, Common, _127_; Crested, 125, 125; Marbled, _126_; Spotted, _127_ Newton, E. T., on fossil Reptiles, 303 n. Nile Crocodile, 461 _Nodosaurus_, _430_ Nose-horned Viper, _640_ _Notaden_, 166, 169; _N. bennetti_, _167_ _Notechis scutatus_, _634_ Nothosauri, _476_ f. Nothosauridae, _477_ _Nothosaurus_, 474; _N. mirabilis_, _477_ Notocentrous vertebrae, defined, 19 Notochord = Chorda dorsalis, _q.v._ _Nototrema_, _189_; _N. cornutum_, _203_; _N. marsupiatum_, _202_; _N. oviferum_, _202_; peculiar gills of embryos, 203; _N. pygmaeum_, _202_; _N. testudineum_, _202_ Nuchal plate of Chelonia, 323 f.; of Pleurodira, 389 Nuchal shield of Chelonia, 326, 327; of Pleurodira, 389, 399 Nuptial excrescences of Anura, 33 Nursing, habits, of _Arthroleptis seychellensis_, 243; of _Chiromantis rufescens_, 244; of _Rhacophorus_, 248; of _Rhinoderma_, 228 f.; of _Pipa_, 151; of _Hyla faber_, 196 f.; of _H. nebulosa_, 198; of _H. goeldii_, 198; of _Nototrema_, 203; of _Phyllomedusa_, 204 f.; of _Leptodactylus_, 219 f.; of eggs by _Desmognathus_, 103, 103; by _Autodax_, 108 _Nyctibatrachus_, _240_ _Nyctimantis rugiceps_, _189_, _206_ _Nyctixalus_, 238
Occipital condyle, of Reptilia, 278; exaggerated importance of, 285; of Theromorpha, 302; of Pareiasauri, 305; of _Cynognathus_, 307; of _Crateronotus_, 307; of _Dicynodon_, 310; of Eusuchia, 437; of Amphisbaenidae, 496 Odontaglossa, 140 _Oligodon_, dentition, 593 n. _Omosaurus_ = _Stegosaurus_, _425_ {662} Omosternum of Anura, 25; taxonomic value, 141 _Onychodactylus_, 96; _O. japonicus_, _109_ Operculum of gills, 44 _Ophiderpeton_, _81_ Ophidia, 491, _581_ f. _Ophiophagus_, _632_ _Ophiops_, 551 _Ophioxylon_ (plant), 629 _Ophisaurus_, _538_; _O. apus_, _538_; _O. gracilis_, _538_ _Ophthalmosaurus_, limbs, 481, 481, 484 Opisthocoelous, definition, 12 Opisthoglossa, 140 Opisthoglypha, _592_, _606_ f., _623_ f. Oppel, on classification, 7 _Oreobatrachus_, _241_ _Oreophrynella_, _227_ _Ornithocheirus_, _486_ _Ornithomimus_, 417; _O. grandis_, _429_ Ornithopoda, 425, _426_ _Ornithopsis_, _419_ Ornithoscelida, 416 _Ornithosuchus_, _433_ _Orthocosta_, 288, _289_ Orthopoda, _424_ Ossifications, dermal, in Anura, 31, 34, 179, 190, 210, 211 Osteoderms = ossifications in the skin, of _Sphargis_, 337; of _Caiman_, 337; of Lizards, 504, 513, 514 _Osteolaemus_, _450_; _O. tetraspis_, _466_ Ouaran, _543_ _Oudenodon_, 301; _O. rugosus_, _310_ Ovary, 49 Oviduct, 49, 51 Owen, on fossil Reptiles, 303 n. Oxydactyla, 140 _Oxyglossus_, 239, _241_
_Pachytriton_, 96, _115_; _P. brevipes_, _132_ Painted Terrapin, _347_, 348; rate of growth, 349 _Palaeobatrachus_, vertebral column, 22, 145 _Palaeohatteria longicaudata_, _291_; skull, 280, 304 _Paludicola_, resembles _Engystomops_, 166, _212_, _220_; _P. fuscomaculata_, 220; _P. biligonigera_, 221 _Paludina_, as food of _Trionyx_, 407 Parasternum = the sum total of the Abdominal ribs, _q.v._; of _Sphenodon_, 298; of Crocodilia, 440; of Ichthyosauria, 480 Parasuchia, _433_ Pareiasauri, 301, 302, _304_ _Pareiasaurus baini_, _304_ Parrots, feathers dyed with poison of _Dendrobates_, 272 _Pelobates_, variation of vertebrae, 19; sacral vertebra, 22, _161_ f.; _P. fuscus_, _162_; _P. cultripes_, _163_, 164; _P. syriacus_, _164_ Pelobatidae, _139_, _160_ f.; distribution, 161 _Pelodytes_, _161_, _165_; _P. punctatus_, _165_; _P. caucasicus_, _166_ _Pelomedusa galeata_, _391_ Pelomedusidae, _313_, _314_; distribution, 332, _390_ f. _Pelosaurus_, _81_ Pelvic, plexus of Anura, 39 Pelvis, of Urodela, 15; of Anura, 22, 27; of _Eryops_, 286; of Microsauri, 289; of _Sphenodon_, 298; of Theromorpha, 302; of Pareiasauri, 305; of _Cynognathus_, 307; of _Dicynodon_, 310; of Chelonia, 319, 319, 320; of Pleurodira, 388, 389; of Dinosauria, 414; of Eusuchia, 441; of Plesiosauria, 476; of Ichthyosauria, 480; of Pterosauria, 485; of Pythonomorpha, 489; of Lacertilia, 496 Perennibranchiata, 8, 9; not a natural group, 65 Petrels living with _Sphenodon_, 299 _Petrobates_, 288, _289_ Phalanges, number of, in Urodela, 15; in Anura, 26, 27, 238; in Stegocephali, 79; in _Palaeohatteria_, 291; in Chelonia, 320, 321; in _Chelone_, 379; in _Scelidosaurus_, 425; in _Camptosaurus_, 427; in _Laosaurus_, 427; in _Iguanodon_, 428; in Eusuchia, 441; in Plesiosauria, 475; in _Lariosaurus_, 477; in Ichthyosauria, 481, 481; in Pterosauria, 485, 485; shape in Anura, 138; peculiar in _Pipa_, 151 Phaneroglossa, _152_ Phanéroglosses, 139 _Phanerotis_, _213_ Phisalix, on poison of Amphibia, 37 _Pholidosaurus_, _451_ Phractamphibia, _78_ f. Phrynaglosses, 139 _Phrynella_, _227_; _Ph. pollicaris_, 233 _Phryniscus_, 226, _227_, _230_; _Ph. nigricans_, _230_ _Phrynobatrachus_, _241_ _Phrynocara_, 235, _236_ _Phrynocephalus_, _521_; deserticolous, 493; coloration, 494; _Ph. helioscopus_, _522_; _Ph. interscapularis_, _522_; _Ph. mystaceus_, _522_ _Phrynoderma_, _241_ _Phrynomantis_, 226, _228_ _Phrynopsis_, _241_ _Phrynosoma_, 305, _533_; _Ph. coronatum_, _534_, 535; _Ph. cornutum_, _533_, 534 _Phyllobates_, _242_; _Ph. bicolor_, _242_; _Ph. trinitatis_, _242_ _Phyllodactylus_, _507_; _Ph. europaeus_, _507_ _Phyllodramus_, 238, _242_ _Phyllomedusa_, _189_, _203_ f.; _Ph. bicolor_, _203_; _Ph. dacnicolor_, _203_; _Ph. hypochondrialis_, breeding habits and development, _204_; {663} _Ph. iheringi_, _205_; breeding habits, 206 Phylogeny, of Amphibia, 66; of Anura, 142 f.; of Reptilia, 282; of Lacertilia, 515; of Ophidia, 592 _Physignathus lesueuri_, _523_, 524 Pigment in the skin, 34 _Pipa_, 143, 144, _149_ f., 150 Pit-Vipers, _644_ Placodontia, _311_ _Placodus_, 301; _P. gigas_, _311_ Plastron, of Chelonia, 315, 321, 321; provided with hinges, 323; sexual characters of, 331; movable in _Emys_, 350; of Chelonidae, 321, 321, 322, 380; of Pelomedusidae, 390; of Chelydidae, 399; of Trionychoidea, 406 _Platecarpus_, _490_ _Platemys_, suppression of neural plates, 324; skull, 399 Plathander = _Xenopus_, _146_ f. _Platurus fasciatus_ s. _colubrinus_, _637_ Platydactyla, 140 _Platydactylus facetanus_, _509_, 508 _Platyhyla_, _236_ _Platypelis_, 235, _236_ Platysternidae, _314_, 326, _345_ _Platysternum megacephalum_, _345_ _Plectromantis_, _212_ _Plesiochelys_, 380, 389 Plesiosauri, _477_ f. Plesiosauria, _473_ f.; vertebrae, 474 Plesiosauridae, _478_ _Plesiosaurus_, 475, _478_; _P. conybeari_, _478_; _P. dolichodirus_, _478_ _Plethodon_, 94, 96, _104_, _106_; _P. erythronotus_, _107_; _P. glutinosus_, _106_ Plethodontinae, 102, _103_ _Plethodontohyla_, 235, _236_ Pleurodira, _313_, _388_ f. _Pleurosaurus_, _294_ _Pleurosternum_, 390 _Plioplatecarpus_, _489_ Pliosauridae, _477_ _Pliosaurus grandis_, _477_ Plover, Egyptian, and Crocodile, 462 _Podocnemis_, 390, _391_; _P. expansa_, _391_ f.; Bates, on habits of, 392 f. Poikilothermous, defined, 67 Poison, of Amphibia, 37, 38; peculiar use of, 272 Poison-apparatus, of _Heloderma_, 540; of Snakes, 586 f. _Polacanthus_, _425_ _Polychrus marmoratus_, _529_ _Polyodontophis_, _605_ n. Portschinsky, on parasitic flies, 177 n. Postpubis, of Dinosaurs, 414, 424, 426 Pouchet, quoted, 571 Predentary bone, of Dinosaur, 424 Prehallux, of Anura, 28 Prepubis, of Dinosaurs, 414, 424, 426 _Proganochelys_, 389 Proganosauria, 476 Proreptilia, _285_ Prosauri, _290_ Prosauria, _288_ _Prostherapis_, _242_ Protection of Amphibia by poison, 38 Proteidae, 94, 96, _132_ f. Proteroglossa, 140 Proteroglypha, _625_ _Proteus_, 96; _P. anguinus_, _133_, 134 Protorosauri, _290_, 304 _Protorosaurus lincki_, _291_ _Protosphargis_, 336 _Protostega_, 336 _Protriton_, _80_, 81 _Psammodromus hispanicus_, _558_; _P. algirus_, _558_ _Psammosaurus_, _543_ _Psephoderma_, 337 _Psephophorus_, 336, 337 _Pseudechis porphyriaceus_, _634_ _Pseudis_, _212_, _213_; _P. paradoxa_, _213_ f. _Pseudobranchus_, 96; _P. striatus_, 137 Pseudocentrous, defined, 79 _Pseudophryne_, 166, _167_, _168_; spawning, 223; _P. australis_, _168_; _P. bibroni_, _168_ _Pseudopus_, aberrant scaling, 495; _P. pallasi_, _538_ _Pseudosphargis_, 336 _Pseudosuchia_, _432_ _Ptenopus_, _507_; deserticolous, 494 _Pteranodon longiceps_, _487_ Pteranodontes, _487_ _Pternohyla_, 179, _189_; _P. fodiens_, _207_ Pterodactyli, _486_ _Pterodactylus longirostris_, _487_; _P. spectabilis_, _487_ Pterosauri, _486_ Pterosauria, _484_ f. _Ptyas_ = _Zamenis_, _611_ _Ptychozoon_, tail, 506; _P. homalocephalum_, _512_, 512; adhesive apparatus, 505 Pubis, of Dinosaurs, 414, 424, 426 Puff Adder, _639_, 639 Pygopodidae, _514_, _567_ _Pygopus lepidopus_, _567_ _Python_, _598_; _P. molurus_, _600_, 600; _P. regius_ = _P. sebae_, _601_; _P. reticulatus_, _598_; _P. spilotes_, _598_, 599 Pythoninae, _598_ f. Pythonomorpha, _487_ f. _Pyxis arachnoides_, _365_
Radde's "law of the steppe," 493 _Rana_, _241_, _249_ f.; sacral vertebrae, 22; shoulder-girdle, 25; urino-genital organs, 49; Tadpoles' horny teeth, 58; vocal sacs, 250; nuptial excrescences, 250; large glandular complexes, 250; distribution, 251; species with finger-discs, 250; _R. afghana_, 250; {664} _R. agilis_, _257_; _R. albolabris_, 250; _R. alticola_, 250; _R. arvalis_, _257_; _R. catesbiana_, _261_; _R. chalconota_, 250; _R. chloronota_, 250; _R. clamata_, _262_, 263; _R. corrugata_, 250; _R. curtipes_, 250; _R. cyanophlyctis_, 250; _R. elegans_, 250; _R. erythraea_, _250_; _R. esculenta_, _263_; mechanism of tongue, 268; vocal sacs, 269; var. _chinensis_, _267_; var. _lessonae_, _265_; var. _ridibunda_, _264_; var. _typica_, _265_; _R. fontinalis_, _262_; _R. glandulosa_, 250; _R. gracilis_, _261_; _R. graeca_, _259_; _R. guppyi_, _261_; _R. halecina_, _263_; _R. hexadactyla_, 250; _R. iberica_, _258_; _R. latastei_, _259_; _R. liebigi_, 250; _R. mascareniensis_, 250; _R. montezumae_, 250; _R. mugiens_, _261_; _R. opisthodon_, _260_; _R. oxyrhynchus_, 250; _R. rugosa_, 250; _R. silvatica_, _259_; _R. temporalis_, 250; _R. temporaria_, _251_ f., 255; _R. tigrina_, _261_ Ranidae, _139_, _237_ f. _Ranidens_, 96; _R. sibiricus_, _109_ Raniformes, 139, 140 Raninae, _139_, _237_, _238_ f.; distribution, 239 _Rappia_, _241_ Rat Snake, _611_, 612 Rattle of Rattle-Snake, 644 Rattle-Snake, _648_ f., 648, 650 Reduction of limbs, in Urodela, 16; in Lacertilia, 497 Regeneration, in Amphibia, 66 f.; of tail in _Sphenodon_, 298; of shell in Chelonia, 329; of horny shields in Chelonia, 329, 386; of tail in Lacertilia, 495; of tail in Geckos, 506 Regions, geographical, 74 f. Reproduction of Tortoise-shell, 386 Reptilia, defined, 277; principal characters of, 278; classification of, 279; diagram of affinities of principal groups, 282; affinities to Mammalia, 303, 309 Respiration, mode of, in Chelonia, 331; assisted by anal sacs, 330 Respiratory organs, of Amphibia, 40 Rhachiodontinae, _622_ _Rhacophorus_, 151, 186, 238, _241_, 244, 246; _Rh. leucomystax_, _247_; tadpoles, 249; _Rh. maculatus_, nesting, 248; _Rh. madagascariensis_, _245_; _Rh. maximus_, _245_; _Rh. pardalis_, _246_, 246; _Rh. reinwardti_, _247_; _Rh. reticulatus_, _248_; _Rh. schlegeli_, nesting, 248 _Rhampholeon spectrum_, _580_ _Rhamphorhynchus longicaudatus_, 486; _Rh. phyllurus_, _486_; _Rh. muensteri_, 487 _Rhamphosuchus crassidens_, _453_ _Rhinatrema_, _89_ _Rhinemys_, 389, 399 _Rhinochelys_, 390 _Rhinoderma_, 226, _227_, _228_; _Rh. darwini_, _228_ f. _Rhinophis_, 91; _Rh. sanguineus_, _596_ _Rhinophrynus_, 166, _168_; _Rh. dorsalis_, _185_, 227 _Rhinophrys_, 167 _Rhombophryne_, 225, _227_ Rhynchocephali, _292_ _Rhynchosaurus_, _292_ _Rhytidosteus_, _83_ Ribs, of Urodela, 14; of Anura, 21; of Microsauri, 288; of _Sphenodon_, 297; of Theromorpha, 302; of _Cynognathus_, 307; of _Microgomphodon_, 309; of Chelonia, 315, 320, 324; of Dinosauria, 413; of Crocodilia, 438; of Parasuchia, 434; of Eusuchia, 439; of Lacertilia, 495; of Geckones, 504; much elongated in certain Iguanidae, 529; meeting ventrally in Chameleons, 568 Ridewood, on hyoid apparatus of Anura, 31 Ringhals, _632_, 633 Ritter and Miller, on _Autodax_, 107 Robinson, on peculiar use of _Varanus_, 546 Rodriguez, gigantic tortoises, 374 Rostral bone of Ceratopsia, 430 Round Island snake, 603
Sacral vertebrae of Anura, 21, 22 _Salamandra_, _115_ f.; trunk-vertebra, 14; skull, 17; lower jaw, 17; distribution, 96, _115_ f.; _S. atra_, _119_ f.; _S. caucasica_, _121_; _S. maculosa_, _115_ f. _Salamandrella_, 96, _109_; _S. keyserlingi_, _109_; _S. schrenki_, egg-sac, 110 Salamandridae, _94_, _102_ _Salamandrina_, 96, _115_; _S. perspicillata_, _122_; skull, 17 Salamandrinae, _102_, _115_ Sarasin, P. and F., 10; on Coeciliae, 88; on _Ichthyophis_, 90 Sauria, _491_ f. _Saurichnites salamandroides_, _83_ Sauropoda, _418_ Sauropsida, 5, _277_ Sauropterygia, 476 _Saurosternum_, _291_ Scales of Apoda, 87 Scaling, aberrant, 495 _Scaphiophryne_, 225, 226, _227_ _Scaphiopus_, _161_, _164_; _S. solitarius_, _165_ _Scapteira_, deserticolous, 494 Scapula, attached to thoracic vertebrae, 487 _Scelidosaurus_, 416; _S. harrisoni_, _425_ Scheuchzer, on _Homo diluvii testis_, 84 Schlegel, on _Cryptobranchus_, 100 Schuberg, on mechanism of finger-discs of Hylidae, 187 Schwalbe, on _Salamandra atra_, 120 Scincidae, _514_, _559_ f. _Scincus officinalis_, _561_ {665} _Sciurus bicolor_, squirrel, 248 _Scolecomorphus_, _90_ Sea Snakes, _635_ Seeley, on fossil Reptiles, 303 n. _Seeleya_, _81_, _289_ Segmental duct, 49 Sense-organs, of Chelonia, 329 f.; of Crocodiles, 445 f. _Sepedon haemachates_, _632_, 633 _Seps_, _562_ Seychelles, gigantic tortoises of, 373 Shell of Chelonia, 321 f., 319, 320, 321, 322, 323, 327;
## partial regeneration of, 329;
correlated changes, 328 Shields, horny, of Chelonia, 322, 323, 325 f., 327; evolution of, 326 f.; individual variation in, 326, 327; periodical peeling of, 328 Shoulder-girdle, of Urodela, 14; of Anura, 24, 25, 138 f.; arciferous, 24, 25, 138; firmisternal, 24, 25, 138; of Aglossa, 144; of Microsauri, 289; of Protorosauri, 290; of Theromorpha, 302; of Pareiasauri, 305; of _Dicynodon_, 310; of Chelonia, 318, 319, 320; of Dinosauria, 414; of Eusuchia, 440; of Plesiosauria, 474; of _Cryptoclidus_, 475; of Ichthyosauria, 480, 481; of Pterosauria, 485; of _Pteranodon_, 487; of Pythonomorpha, 488; of Lacertilia, 496 Shufeldt, on Axolotl, 114; on _Heloderma_, 540 n. _Simosaurus_, _477_ _Siphonops_, 86, 87, _90_ _Siredon_ (Axolotl), 112 _Siren_, 96; _S. lacertina_, 136, 136 Sirenidae, _94_, 96, _136_ _Sistrurus miliarius_, _647_ Skeleton, figured, of _Testudo_, 319; of _Chelone_, 320; of _Brontosaurus_, 418; of _Ceratosaurus_, 422; of _Stegosaurus_, 426; of _Iguanodon_, 428; of _Triceratops_, 430; of _Pterodactylus_, 485 Skin, of larval Amphibia, 31; shedding of, 32; glands, 32; pigment, 34; change of colour, 35; poison, 36; of Apoda, 87; of _Pipa_, 149; forms receptacles for eggs, 151, 248; of Eusuchia, 441 f. Skin-glands, of Crocodiles, 443; of Lacertilia, 497; of Geckones, 504; of Snakes, 583 Skull, of Urodela, 16 f., 17; of _Amblystoma_, 17; of _Salamandrina_, 17; of _Salamandra_, 17; of Anura, 28 f.; of Apoda, 84, 85 Skull, of Reptilia, 280, 281: –of Proreptilia: _Cricotus_, 287; _Eryops_, 286: –of Microsauri, 289: –of Protorosauri, 280; _Palaeohatteria_, 280, 291: –of Rhynchocephali (_Sphenodon_), 280, 295, 295: –of Theromorpha, 280, 301, 303; _Elginia_, 280, 305 f.; _Cynognathus_, 280, 306; _Gordonia_, 280, 310; _Dicynodon_, 280, 310; Theriodontia, 306; Mammalian resemblances, 308 f.; _Lycosaurus_ 307; _Endothiodon_, 307; _Gomphognathus_, 308; Anomodontia, 309, 280; _Oudenodon_, 310; _Placodus_, 311: –of Mammalia, generalised, 281: –of Chelonia, 316 f., 280; _Sphargis_, 335; Chelydridae, 280, 338; _Chelydra_, 280, 338; Chelonidae, 317, 378, 379; _Chelone_, 317, 378; _Thalassochelys_, 379; _Clemmys_, 356; _Testudo_, 364; _Chelys_, 400, 344; _Trionyx_, 405, 404; _Chrysemys_, 280, 346; _Cistudo_, 280, 361; Pleurodira, 388, 400; Pelomedusidae, 390; Chelydidae, 399, 400; Trionychoidea, 404, 405: –of Dinosauria, 412 f., 422; _Anchisaurus_, 421; _Ceratosaurus_, 422; _Diplodocus_, 419: –of Crocodilia, 280; Pseudosuchia, 432; Parasuchia, 433; Eusuchia, 434 f.; _Gavialis_, 452; _Crocodilus americanus_, 466; _C. niloticus_, 460; _C. palustris_, 455; _C. porosus_, 458; _Alligator_, 468: –of Plesiosauria, 473; _Nothosaurus_, 477: –of Ichthyosauria, 479; _Ichthyosaurus_, 281: –of Pterosauria, 484; _Dimorphodon_, 281: –of Pythonomorpha, 488; _Clidastes_, 281: –of Lacertilia, 281; Geckones, 504; Agamidae, 281, 515; _Uromastix_, 281; Iguanidae, 528; Anguidae, 537; Helodermatidae, 540; Varanidae, 281, 542, 543; _Varanus_, 281; Tejidae, 547; Lacertidae, 281, 550, 550; _Lacerta_, 281; Scincidae, 559; Amphisbaenidae, 565; Chamaeleontes, 568, 569: –of Ophidia, 281, 596, 597, 588; _Eunectes_, 596, 597; _Crotalus_, 588 Slow-worm, _539_, 539 Slugs eaten by tortoises, 363 Smell, sense of, of Chelonia, 330 Smith, the, = _Hyla faber_, peculiar nursing habits, 196 f. Smooth Snake, _619_, 620 Snakes, _581_ f.; skull, 581 f., 281, 588, 596, 597 f.; vertebrae, 582; general anatomical structure, 583 f.; geographical distribution, 585 f., 585; classification, 592 f. Snake-charming, 631 Snake-poison, 586 f. Snake-stones, 629 f. Snapping Turtle, _338_ f. Soft-shelled Turtle, 408 Sound produced by rubbing of scales of _Teratoscincus_, 507 Spade-foot, _162_ _Spelerpes_, 94, 96, 97, _103_, _104_, 106; _S. altamazonicus_, _104_; _S. bilineatus_, _104_; _S. fuscus_, _104_, _105_; tongue, 106; _S. infuscatus_, _104_; _S. lineolus_, _104_; _S. parvipes_, _104_; {666} _S. porphyriticus_, _105_; _S. salmoneus_, _105_; _S. subpalmatus_, _104_; _S. uniformis_, _104_ Spencer, on habits of _Chiroleptes_, 221 f. Spermatophores, 53, 128 Spermatozoa of Amphibia, 52 f. Sphargidae, _313_, _314_, _333_ f.; affinities, 336; morphology of shell, 337 _Sphargis coriacea_, _333_ f., 334; absence of horny shields, 325 _Sphenodon_, 288, 290, 305, 306, 432; _S. punctatum_, 293, _294_; skull, 295; cervical vertebrae, 297; habits, 298 f. _Sphenophryne_, 225, _227_ _Sphenosaurus_, _82_, 287 Spiny-tailed Lizard, _524_ f. Spiracle, development, 45 Spotted Newt, _127_ Spy-Slange, _632_ St. Helena, gigantic tortoises introduced, 375 _Stagonolepis_, _434_ Stannius, 8, 139; on vertebrae of _Pelobates_, 20 _Staurotypus salvini_, _342_ Stegocephali, 78 f.; St. Lepospondyli, _80_ f.; St. Temnospondyli, _81_ f.; St. Stereospondyli, _83_ f.; vertebrae, 78 f.; shoulder-girdle, 79; dermal armour, 79 Stegosauri, _425_ _Stegosaurus armatus_, _425_; _S. ungulatus_, _426_, 426 _Stenodactylus_, deserticolous, 494; sleeping attitude, 509 _Stereocyclops_, _227_, _231_; _S. incrassatus_, _231_ _Stereorhachis_, _308_ Stereospondylous vertebrae, defined, 284 _Sternothaerus_, 324, 389, _390_; _S. derbianus_, _391_; shields of, 327 Sternum, of Urodela, 15; of Anura, 25; taxonomic value, 141, 142; of _Sphenodon_, 297 f.; Protorosauri, 290; Dinosauria, 414; Eusuchia, 440 Stewart, quoted, on _Heloderma_, 540 n. Stinkpot Terrapin, 342 Suboccipital (first spinal nerve) of Anura, 144 Subregions, geographical, 74 f. Surinam Toad, 149, 150 _Syrrhopus_, 212 Systomata, 139
Tadpoles, horny teeth of, 58 f.; of _Megalophrys_, 59, 60; absorption of tail, 61 f.; of _Xenopus_, 147, 148; of _Bombinator_, 157; of _Alytes_, 159; of _Hyla arborea_, 193; of _H. versicolor_, 195; of _Bufo viridis_, 181; of _B. calamita_, 183; of _B. vulgaris_, 176; of _Thoropa miliaris_, 209; of _Pseudis paradoxa_, 213; of _Hylodes martinicensis_, 214; of _Rhinoderma darwini_, 229; of _Arthroleptis seychellensis_, 243; of _Rana temporaria_, 255; of _R. opisthodon_, 260; of _R. esculenta_, 270 Tail, of Anura, 21, 24; its absorption, 61; of Chelonia, 328; of Geckos, various shapes, 506; reproduction of, 506 _Tarentola mauritanica_, 508, _509_ f. Tarsus (_see_ also Limbs), of Chelonia, 319, 320, 321; of Dinosauria, 416, 418, 420, 421, 423, 426; of Theropoda, 420; of _Compsognathus_, 423; of _Iguanodon_, 428 Teeth, of Anura, 30, 138, 139; substitutes for, 30, 58, 218, 237; of Apoda, 86; of _Rhynchosaurus_, 292; of _Homoeosaurus_, 292; of Rhynchocephali, 292; of _Sphenodon_, 296; of Theromorpha, 301; of _Elginia_, 306, 280; of _Cynognathus_, 306, 280; of _Lycosaurus_, 307; of _Galesaurus_, 307; of _Endothiodon_, 307; of _Empedias_, 308; of _Stereorhachis_, 308; of _Gomphognathus_, 308; of _Tritylodon_, 309; Mammalian resemblances, 309; of Anomodontia, 309; of _Dicynodon_, 280, 310; of _Gordonia_, 280; of _Placodus_, 311; of Sauropoda, 418 f., 419; of Theropoda, 420 f., 422; of Orthopoda, 424 f.; of Eusuchia, 437; of Ichthyosauri, 479; of Snakes, 582 Tejidae, _514_, _547_ f. Teju, _548_, 548 Teleosauridae, _450_ _Teleosaurus_, _451_ _Telerpeton elginense_, _291_ Temnospondylous vertebrae, defined, 284 Temperature of blood, 67 f.; of water for Crocodiles, 460 Tennent, on immunity of Cobras, 629 f.; on turtles at Ceylon, 384, 386; on habits of _Crocodilus palustris_, _456_ f.; on habits of _C. porosus_, 459; on peculiar use of _Varanus_, 545; on habits of Gecko, 511 Tentacular apparatus of Apoda, 45, 86, 88 _Tephrometopon_, 493 _Teratoscincus_, deserticolous, 493; eye, 494; _T. scincus_, _507_ Terrapin, _359_ f. Testis, 49 Testudinidae, _313_, _314_, _345_; distribution, 332 _Testudo_, 365; skeleton, 322, 323; shields of, 327; _T. abingdoni_, 376, _378_; _T. atlas_, 372, 377; _T. daudini_, _375_, 376; _T. elegans_, _370_ f.; _T. elephantina_, _374_; _T. elephantopus_, _378_; _T. ephippium_, _378_; _T. gigantea_, _374_; _T. graeca_, _365_ f.; habits, 367; eggs, 369; great age, 369; _T. grandidieri_, 373; _T. horsfieldi_, _370_; _T. ibera_, _366_; age attained, 369; rate of growth, 370; _T. marginata_, _367_; _T. perpigniana_, 372; _T. polyphemus_, _371_ f.; {667} _T. sumeirei_, _376_; _T. vosmaeri_, 373, 377 _Tetradactylus_, _559_; _T. africanus_, _559_; _T. seps_, 559 Tetrapoda, Credner's name for "four-footed" creatures in opposition to the fishes, which have fins, 4, 11 Thalassemydidae, 380 _Thalassochelys caretta_, individual variation of shields, 326, 327, _387_; skull, 379 Thecophora, definition of term, 337, _338_ Theobald, on _Varanus_, 544 Theriodontia, _306_ Theromorpha, _300_, 301; skull, 280, 301; their affinity to Mammals, 303 f., 309 Theropoda, _420_ Thilenius, quoted, 571 n. _Thoracosaurus_, _451_ _Thorius_, 96, _103_; _Th. pennatulus_, _103_ _Thoropa_, 186, _189_; _Th. miliaris_, _209_ Tiger Snake, _634_ _Tiliqua_ s. _Cyclodus_, _561_ Toad, _see_ Bufo, 169; common Toad, 170, 172 Toes, number of, in Urodela, 16; in Anura, 28; of Geckos, structure, 505, 505 _Tomistoma_, 435, _450_; _T. schlegeli_, _453_ Tongue, of Amphibia, nerve-supply, 39; shape of, in Anura, 47; of _Spelerpes_, 106; absent in Aglossa, 145; of _Rana esculenta_, 268; of Crocodiles, 443; of Lacertilia, 498; of Chameleons, 569 f. Tortoise, Greek, _365_ f.; habits, 367 f.; Moroccan, _366_; habits, 367 f.; Starred, _370_ f.; Gopher, 371 f.; Gigantic Land-Tortoises, 372 f. Tortoises = Chelonia, _312_ f. Tortoise-shell of commerce, 386 Trachea, of Crocodiles, 443 _Trachysaurus_, 560, _560_; _T. rugosus_, _560_, 561 Tree-frogs, 185 f.; change of colour, 35 _Trematosaurus_, 80, _83_ _Triceratops_, 413; _T. prorsus_, _430_, 430; _T. flabellatus_, _430_ _Trichobatrachus_, _240_; _T. robustus_, _271_ _Trigonocephalus cenchris_, _645_, 645, _646_, 646 _Trimerorhachis_, _82_ Trionychidae, _313_; distribution, 333 Trionychoidea, _313_, _314_, _404_ f.; habits, 407 _Trionyx_, nuchal plate, 324; skull, 405; plastron, 406; number of costal plates, 325; _T. ferox_, _408_, 409; _T. formosa_, _411_, 411; _T. gangeticus_, _410_, 410; _T. hurum_, 410; _T. triunguis_, _410_ _Triprion_, 179, 185, _189_; _T. petasatus_, _207_ _Trirhachiodon_, _309_ _Triton_, _122_ f., 96, _115_, 125, 128, 131; fossil, 83; spermatophores, 53; _T. alpestris_, 123, _126_; _T. asper_, 123, _130_; _T. blasii_, _126_; _T. boscai_, 123, _127_; _T. cristatus_, 122, _125_, 125; _T. hagenmuelleri_, 123; _T. helveticus_, _127_; _T. italicus_, _127_; _T. marmoratus_, 122, _126_; _T. montadoni_, _127_; _T. montanus_, 123, _130_; _T. palmatus_, _127_; _T. poireti_, 123; _T. punctatus_ = _vulgaris_, _127_; _T. pyrenaeus_, _130_; _T. pyrrhogaster_, 123, _128_; _T. rusconii_, 123, _130_; _T. sinensis_, 123, _128_; _T. taeniatus_ = _vulgaris_, _127_; _T. torosus_, 123, _128_; _T. viridescens_, 123, _128_; egg, 128; _T. vittatus_, 122, _128_; _T. vulgaris_, 123, _127_; _T. waltli_, 123, _130_, 131 _Tritylodon_, 301, _309_ _Tropidonotus_, _607_; _T. natrix_, _608_ f.; _T. ordinatus_, _611_; _T. sirtalis_, 610, _611_; _T. tesselatus_, _611_ _Tropidosaura_, _558_ Tuatera, 293 _Tupinambis_, _548_; _T. teguixin_, _548_; _T. nigropunctatus_, _548_, 548 Turtles, _378_ f.; skull, 317, 379; skeleton, 320; plastron, 321; on Laysan Islands, 383; Green or Edible, _381_ f.; Hawksbill, _384_, 385 _Tylototriton_, 96, _115_; _T. andersoni_, 130; _T. verrucosus_, _132_ Tympanic cavity, reduction of, in Anura, 30; in Ophidia, 583 Tympanum of Aglossa, 143 _Typhlomolge_, 96; _T. rathbuni_, _135_ _Typhlonectes_, 87, _90_; _T. compressicauda_, _93_ Typhlopidae, _592_, _593_ f. _Typhlops_, 91; _T. braminus_, _594_; _T. vermicularis_, _594_ _Typhlosaurus_, _564_ _Typhlotriton_, 94, 96, 102; _T. spelaeus_, _103_
_Uraeotyphlus_, 86, _89_ Ureter, 48 f., 49 Urino-genital organs, 48 f., 49 _Urocordylus_, _81_, 288 Urodaeum of Chelonia, 330 Urodela, _94_ f.; geographical distribution, 96 _Uromastix_, _524_; _U. acanthinurus_, _526_, 526; _U. hardwicki_, _525_ Uropeltidae, _592_, _595_ _Uropeltis_, _595_; _U. grandis_, _595_ _Uroplates_, 512 Uroplatinae, _512_ Urostyle, of Anura, 23; of Chelonia, 328
Varanidae, _514_, _542_ f.; skull, 542; distribution, 543 _Varanus_, _543_; _V. gouldi_, _546_; _V. griseus_, skull, 542; _V. niloticus_, _543_; _V. salvator_, _543_ f., 546 Vas deferens, 48 f., 49 Vertebrae, procoelous, definition, 19, 138; acentrous, _i.e._ without a centre or body, 4; {668} amphicoelous, defined, 12; of Urodela, 11; gastrocentrous, defined, 282; lepospondylous, 5; defined, 78; notocentrous, 4; defined, 19; opisthocoelous, defined, 12, 138; pseudocentrous, 4, 78; stereospondylous, defined, 79, 284; temnospondylous, 13; defined, 79, 284; development of–in Urodela, 12, 13; in Anura, 19; of trunk of _Salamandra_, 14; epichordal, 20; sacral, of Anura, 22; shifting forwards of sacral attachment of ilium, 23; of Reptilia, composition of, 283, 288; trunk-vertebrae of _Eryops_, 283, 286, 286; of _Cricotus_, 287; of Microsauri, 289; of _Sphenodon_, 294, 296, 297; atlas and axis of _Sphenodon_, 283; of Theromorpha, 302; of Pareiasauri, 305; atlas fused with axis in _Cynognathus_, 307; of _Dimetrodon_, with peculiar processes, 308; of Chelonia, 314 f.; atlas of _Trionyx_, 283; of _Chelys_, 283; of Dinosauria, 413; hollow in Dinosaurs, 415, 420; of Eusuchia, 438 f.; atlas and axis of _Crocodilus_, 283; of _Metriorhynchus_, 283; of Pterosauria, 485; of Ichthyosauria, 480; of Pythonomorpha, 488; of Lacertilia, 494; of Geckones, 503; of Snakes, 582 Vertebral column, instance of greatest shortening, 144; of Urodela, 11, 13; of Stegocephali, 78; of Anura, 18 f., 21, 22; _Palaeobatrachus_, 22; _Pipa_, 22, 143; _Hymenochirus_, 22, 143; _Bombinator_, 22; _Xenopus_, 21, 143; of Apoda, 86; number of vertebrae of _Protorosaurus_, 291; of _Palaeohatteria_, 291; of _Homoeosaurus_, 292; of _Sphenodon_, 297; of _Cynognathus_, 306; of _Iguanodon_, 428; of Eusuchia, 440; of Plesiosauria, 474; of Elasmosauridae, 478 Vesiculae seminales, 49, 51 Viper, Common, _641_ f., 620, 642 _Vipera_, _641_; _V. ammodytes_, 641, _643_; _V. aspis_, _643_; _V. berus_, _641_, 642, 620; _V. latastei_, _643_; _V. russelli_, _643_ Viperidae, 592, 593, _637_ Viperinae, _638_ Viperine Snake, _610_ Vis, de, on _Chlamydosaurus_, 523 Viviparous, Chameleon, 572; Lacertilia, 499; Geckos, 506 Vocal sacs, 47 f.; of _Paludicola_, 220; of _Rhinoderma_, used as brood-pouches, 228 Voeltzkow, on nesting of Crocodiles, 462 f.; on _Testudo daudini_, 375 Voice, 47
Wagler, 8 Wallace, on _Rhacophorus_, 246 f. Wall-Lizard, _557_ Warning, attitudes, of _Bombinator_, 157; colours, 38, 116, 156; of _Heloderma_, 541 Water-Viper, _645_, 645 Weismann, on Axolotl, 64, 114 Werner, on _Eryx_, _604_ White's aged Tortoise, 369 Wilder, on _Desmognathus_, 103
_Xantusia_, _547_ Xantusiidae, _514_, _547_ _Xenobatrachus_, 225; _X. ophiodon_, _228_ Xenopeltidae, _593_, _605_ _Xenopeltis unicolor_, _605_ _Xenopus_, 143; distribution, 143, 144, _146_ f.; _X. calcaratus_, 146; _X. laevis_, _146_ f., 147; _X. muelleri_, 146 _Xenorhina_, _228_ Xenosauridae, _513_, _536_ _Xenosaurus grandis_, _536_
_Zachaenus_, _212_ _Zamenis constrictor_, _613_; _Z. gemonensis_ s. _viridiflavus_, _612_; _Z. hippocrepis_, _613_; _Z. mucosus_, _611_, 612 _Zanclodon_, 417, 421 Zander, on habits of _Agama_, 520; of _Phrynocephalus_, 522; of _Eryx_, _604_ _Zaocys carinatus_, _614_, 615 _Zatachys_, _82_ Zeller, on spermatophores, 53; on _Proteus_, _134_ Zonuridae, _513_, _536_ _Zonurus derbianus_ s. _giganteus_, _536_, 537
END OF VOL. VIII
_Printed by_ R. & R. CLARK, LIMITED, _Edinburgh_.
THE CAMBRIDGE NATURAL HISTORY
EDITED BY
S. F. HARMER, Sc.D., F.R.S. and A. E. SHIPLEY, M.A., F.R.S.
_In Ten Volumes. Fully Illustrated. Medium 8vo. 17s. net each._
PROTOZOA, COELENTERATES, ECHINODERMS, etc.
VOLUME I.
PROTOZOA, by MARCUS HARTOG, M.A., D.Sc.; PORIFERA (SPONGES), by IGERNA B. J. SOLLAS, B.Sc.; COELENTERATA AND CTENOPHORA, by S. J. HICKSON, M.A., F.R.S.; ECHINODERMATA, by E. W. MACBRIDE, M.A, F.R.S.
_NATURE._–"Taken in conjunction with the earlier published volumes, the work seems to fulfil the purpose of providing an intelligible and adequate survey of the entire animal kingdom without giving undue prominence to particular groups.... The illustrations are excellent."
_FIELD._–"The book can be in the strongest manner recommended to those for whose benefit it has been written. We know of no work from which a more truly scientific account of the Protozoa, Echinodermata, and other lower forms of animal life could be gained."
_OUTLOOK._–"There is much valuable matter in these well-planned sections which will render the volume, like the others which have preceded it, a necessary book of reference in every well-equipped library."
WORMS, ROTIFERS, AND POLYZOA
VOLUME II.
FLATWORMS AND MESOZOA, by F. W. GAMBLE, D.Sc.; NEMERTINES, by Miss L. SHELDON; THREADWORMS AND SAGITTA, by A. E. SHIPLEY, M.A., F.R.S.; ROTIFERS, by MARCUS HARTOG, M.A., D.Sc.; POLYCHAET WORMS, by W. BLAXLAND BENHAM, D.Sc., M.A.; EARTHWORMS AND LEECHES, by F. E. BEDDARD, M.A., F.R.S.; GEPHYREA AND PHORONIS, by A. E. SHIPLEY, M.A., F.R.S.; POLYZOA, by S. F. HARMER, Sc.D., F.R.S.
_CAMBRIDGE REVIEW._–"Several of the groups treated of in this volume are unknown, by sight even, to the general reader, and possess no popular name whatsoever; and as only a few insignificant details are known of the habits of the animals composing them, their treatment in the volume before us has necessarily been to a large extent anatomical. This circumstance renders the book of especial value to students, more
## particularly as in some cases the articles on the groups in question are
the first comprehensive ones dealing with their respective subjects.... Most of the articles are of a very high order of merit–taken as a whole, it may be said that they are by far the best which have as yet been published.... We may say with confidence that the same amount of information, within the same compass, is to be had in no other zoological work."
_NATURAL SCIENCE._–"This second volume of the Cambridge Natural History is certain to prove a most welcome addition to English Zoological literature. It deals with a series of animal groups, all deeply interesting to the specialist in morphology; some important from their economic relations to other living things, others in their life-histories rivalling the marvels of fairy-tales. And the style in which they are here treated is also interesting; history and the early observations of the older writers lend their charm; accounts of habits and mode of occurrence, of life, in a word, from the cradle to the grave, are given in ample detail, accompanied by full references to modern and current literature. The whole is admirably illustrated."
MOLLUSCS AND BRACHIOPODS
VOLUME III.
MOLLUSCS, by the Rev. A. H. COOKE, M.A.; BRACHIOPODS (RECENT), by A. E. SHIPLEY, M.A., F.R.S.; BRACHIOPODS (FOSSIL), by F. R. C. REED, M.A.
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_FIELD._–"We know of no book available to the general reader which affords such a vast fund of information on the structure and habits of molluscs."
_KNOWLEDGE._–"If succeeding volumes are like this one, the Cambridge Natural History will rank as one of the finest works on natural history ever published."
_ATHENÆUM._–"The series certainly ought not to be restricted in its circulation to lecturers and students only; and, if the forthcoming volumes reach the standard of the one here under notice, the success of the enterprise should be assured."
VOLUME IV.
CRUSTACEA, by GEOFFREY SMITH, M.A.; TRILOBITES, ETC., by H. WOODS, M.A.; LIMULUS, LINGUATULIDA, AND TARDIGRADA, by A. E. SHIPLEY, M.A., F.R.S.; SPIDERS, MITES, SCORPIONS, ETC., by C. WARBURTON, M.A.; PYCNOGONIDS, by D'ARCY W. THOMPSON, C.B., M.A.
[_In the Press._
PERIPATUS, MYRIAPODS, AND INSECTS–PART I.
VOLUME V.
PERIPATUS, by ADAM SEDGWICK, M.A., F.R.S.; Myriapods, by F. G. SINCLAIR, M.A.; INSECTS, Part I., INTRODUCTION, APTERA, ORTHOPTERA, NEUROPTERA, AND A PORTION OF HYMENOPTERA (SESSILIVENTRES AND PARASITICA), by DAVID SHARP, M.A., M.B., F.R.S.
_FIELD._–"Although written for the student and the specialist, the book is not the less adapted to all intelligent readers who wish to make themselves thoroughly acquainted with the habits, structure, and the modern classification of the animals of which it treats. To such it cannot be recommended too strongly."
_SCIENCE GOSSIP._–"Every library, school, and college in the country should possess this work, which is of the highest educational value."
_Prof. RAPHAEL MELDOLA, F.R.S., F.C.S., in his Presidential Address to the Entomological Society of London, said_:–"The authors of this volume are certainly to be congratulated upon having furnished such a valuable contribution to our literature. When its successor appears, and I will venture to express the hope that this will be at no very distant period, we shall be in possession of a treatise on the natural history of insects which, from the point of view of the general reader, will compare most favourably with any similar work that has been published in the English language."
_ENTOMOLOGISTS MONTHLY MAGAZINE._–"We venture to think the work will be found indispensable to all who seek to extend their general knowledge beyond the narrowing influence of exclusive attention to certain orders or groups, and that it will take a high position in 'The Cambridge Natural History' series."
INSECTS–PART II.
VOLUME VI.
HYMENOPTERA _continued_ (TUBULIFERA AND ACULEATA), COLEOPTERA, STREPSIPTERA, LEPIDOPTERA, DIPTERA, APHANIPTERA, THYSANOPTERA, HEMIPTERA, ANOPLURA, by DAVID SHARP, M.A., M.B., F.R.S.
_SATURDAY REVIEW._–"Dr. Sharp's treatment is altogether worthy of the series and of his own high scientific reputation. But in a work of this sort it is not only necessary that information should be accurate, but also that it shall be presented to the eye, so far as illustrations and printing are concerned, in such a way as to render its matter as easily intelligible as possible, and readily usable for purposes of reference. Under both these heads we have nothing but commendation for Mr. Sharp's treatise. The illustrations are indeed beautiful, and the use of the heavy type for the headings of the various sections and leading paragraphs materially helps the reader in the progress of his study. Certainly this is a book that should be in every entomologist's library."
_DAILY NEWS._–"It would be hard to say too much in praise of this most admirable volume. It is too often the case that scientific books are written in a dull and uninteresting style. The reader will find nothing of that kind to complain of here. The descriptions are clear, the illustrations are excellent; while, as in the previous volumes of the series, printing and paper are all that could be desired."
FISHES, ASCIDIANS, etc.
VOLUME VII.
HEMICHORDATA, by S. F. HARMER, Sc.D., F.R.S.; ASCIDIANS AND AMPHIOXUS, by W. A. HERDMAN, D.Sc., F.R.S.; FISHES (EXCLUSIVE OF THE SYSTEMATIC ACCOUNT OF TELEOSTEI), by T. W. BBIDGE[**BRIDGE??], Sc.D., F.R.S.; FISHES (SYSTEMATIC ACCOUNT OF TELEOSTEI), by G. A. BOULENGER, F.R.S.
_ATHENÆUM._–"All who take a serious interest in the advance of ichthyology will find this a fascinating book."
_NATURE NOTES._–"It is a thoroughly scholarly work for students, amply sustaining the reputation of an ancient university as being in the van of scientific progress."
AMPHIBIA AND REPTILES
VOLUME VIII.
By HANS GADOW, M.A., F.R.S.
_FIELD._–"The work is worthy of the series in which it appears, and we cannot give it higher praise."
_SCIENCE GOSSIP._–"More than maintains the high scientific reputation of this series. The herpetologists, or students of the Amphibia and Reptiles, have now a standard work of the highest class."
_LANCET._–"An account of both Amphibia and Reptiles which should satisfy the expert, and at the same time entertain the reader who is merely interested in the tit-bits of natural history.... A book full of accurate information and pleasant reading."
_MORNING POST._–"A delightful as well as a serviceable book.... Herein perhaps lies the great charm and merit of Dr. Gadow's book, that, while satisfying all the inquiries of the student, it is also in great part written for the ordinary intelligence, and the naturalist in the crowd may, while necessarily gliding over distressing technicalities, find in its pages many hours of profitable and entertaining study of the habits of the classes under notice."
_NATURE._–"In concluding the review we would express the opinion that by this handsome volume a very important addition to science has been made; that the beautiful illustrations, together with the clear and charming accounts of the life-histories which it contains, will do much to popularise the study of a rather neglected section of zoology; and that lovers of Reptiles, of which there are more than one generally thinks, will feel that the new knowledge imparted to them emanates from one who is thoroughly in sympathy with their enthusiasm."
BIRDS
VOLUME IX.
By A. H. EVANS, M.A.
_IBIS._–"Mr. Evans has produced a book full of concentrated essence of information on birds, especially as regards their outer structure and habits, and one that we can cordially recommend as a work of reference to all students of ornithology."
_NATURE NOTES._–"We venture to predict that, of the ten volumes of which this excellent series is planned to consist, none will secure a wider popularity than Mr. Evans's treatise on birds. Strange as it may appear, among the many books on birds that have appeared of late years, we do not recall any that covers the same ground.... We are grateful to the author for the mine of valuable information which he has crowded between his two covers."
_SCIENCE GOSSIP._–"General readers will find this work most useful in obtaining a proper understanding of birds, and will be assisted by the effective diagram of a hawk in the introduction, showing the recognised names of every part of the exterior appearance. The expressions used in naming the various portions are fully explained on the adjoining page. As we have already said, the illustrations are admirable. The book is a useful addition to any library, as it treats of nearly every known kind of bird throughout the world."
_SATURDAY REVIEW._–"The expert and the novice alike must be at once delighted by the accuracy and the beauty of the illustrations.... It is astonishing to note the mass of information the author has been able to bring together.... With a little practice any observant person would soon learn by the help of this volume to track down any bird very nearly to its ultimate place in classification."
MAMMALIA
VOLUME X.
By FRANK EVERS BEDDARD, M.A., F.R.S.
_NATURE._–"Cannot fail to be of very high value to all students of the Mammalia, especially from the standpoints of morphology and palæontology."
_ATHENÆUM._–"Mr. Beddard has produced a volume equal in interest and value to the others in the Cambridge series."
_LAND AND WATER._–"A notable book, the result of long study, patient labour, sound reasoning, and careful selection, for which we are deeply indebted to the author."
_DAILY NEWS._–"A volume which, for the interest of its contents and for its style and method of treatment, is not only worthy of its predecessors, but may be regarded as one of the most successful of a brilliant series."
_KNOWLEDGE._–"In this volume Mr. Beddard has undoubtedly made an important contribution to the history of mammals, his text-book being the only one which can be said to be up to date and to contain notices of the many important types–both recent and fossil–discovered during the last few years."
_FIELD._–"Its utility to the working zoological student can hardly be overrated. It is exceedingly well illustrated."
LONDON: MACMILLAN AND CO., LTD.
----
NOTES
[1] References to explanations of the terms used below will be found in the index.
[2] _Bull. Soc. Philom._ ii. p. 81.
[3] _Tableaux méthodiques_, p. 61.
[4] _Bull. Soc. Philom._ p. 113.
[5] _Isis_, 1821.
[6] Treviranus' _Zeitschr. f. Physiol._ 1831, p. 190.
[7] δέρη, neck; μύω, close.
[8] _Proc. Ac. Philad._ p. 209.
[9] _Americ. Natural._ xxiii. p. 849.
[10] Sarasins' _Ergebnisse ... Ceylon_, 1887-1890.
[11] Credner's term for all Vertebrates higher than fishes.
[12] Boulenger, _P.Z.S._ 1888, p 204.
[13] _P.Z.S._ 1897, p. 577.
[14] _Q.J.M.S._ xxxviii. 1896, p. 465.
[15] _Arch. ges. Physiol._ li. 1892, p. 455.
[16] _Nat. Sci._ i. 1892, p. 185.
[17] _C. R. Ac. Sci._ cix. 1889, pp. 405, 482.
[18] Orr, _Quart. J. Micr. Sci._ xxix. 1889, p. 316.
[19] "Lungenlose Salamandriden," _Anat. Anz._ 1894, p. 676; 1896, p. 182.
[20] "Nuove ricerche anatomo-fisiologiche intorno ai Salamandridi normalmente apneumoni." Torino, 1894.
[21] _Zool. Anz._ 1896, p. 33; 1899, p. 545.
[22] _Amer. Natural_, xxx. 1886, p. 829.
[23] For the mechanism of the frog's respiration, see Gaupp, _Arch. Anat._ 1896, p. 239.
[24] Boulenger, _The Tailless Batrachians of Europe, Ray Soc._ 1896.
[25] _Zeitschr. wiss. Zool._ xlix. 1889, p. 583.
[26] _Amer. Natural_, xxv. 1891, p. 753.
[27] _Zool. Jahrb. Syst._ vi. 1892, p. 447.
[28] _Ann. Nat. Hist._ (5), xvii. 1886, p. 463.
[29] J. Thiele, _Zeitschr. wiss. Zool._ xlvi. 1888, p. 67.
[30] _Zeitschr. wiss. Zool._ xlix. 1889, p. 43.
[31] M. Weber, _Ann. Jard. Botan. Buitenzorg_, Suppl. ii. 1898, p. 5.
[32] For "A Synopsis of the Tadpoles of European Batrachians," see Boulenger, _P. Z. S._ 1891, pp. 593-627, pls. xlv.-xlvii.; also Bedriaga, "Tableaux synoptiques pour servir à la détermination des larves des Batraciens Urodèles," _C. R. Ass. Franç. Sci._ ii. 1891, pp. 540-546.
[33] _Arch. mikr. Anat._ xxix. 1887, p. 1.
[34] _Arch. per zool. e per l'anat. comp._, Genova, 1861, p. 206.
[35] _Ann. sci. nat._ (5), vii. 1876.
[36] _Mem. Acc. Torino_, xxxv. 1883, and _Atti Acc. Torino_, xvii. 1883, p. 84. See also Woltersdorff, _Zool. Garten_, 1896, p. 327.
[37] _Verh. Ges. Basel_, vii. 1882, p. 387.
[38] Barfurth, _Arch. Entwickmech._ I. 1895, p. 117.
[39] _The Horn Scientific Expedition_, 1897, p. 155.
[40] _Amer. Natural._ xxix. 1895, p. 998.
[41] _J. Morphol._ xi. 1895, p. 375.
[42] _P. Z. S._ 1895, p. 401.
[43] P. and F. Sarasin, "Zur Entwicklungsgeschichte der ceylonesischen Blindwühle, _Ichthyophis glutinosa_." _Ergebnisse naturwiss._ _Forschungen auf Ceylon_, 1887-1890, vol. ii.
[44] "Beiträge zur Kenntniss der Entwicklungsgeschichte und der Anatomie der Gymnophionen," _Zool. Jahrb. Anat._ x. 1897, p. 389, and xii. 1899, p. 477.
[45] The existence of such a form as _Typhlotriton_, in the adult of which the eyes become closed up, makes such short diagnoses of the families defective, although there is no doubt about the Desmognathine affinities of this genus. See p. 103.
[46] _J. Coll. Japan._ i. 1887, p. 269.
[47] _J. Morphol._ xi. 1895, p. 375.
[48] _Amer. Natural._ xxxiii. March 1899, p. 231.
[49] _Amer. Natural._ March, 1899, p. 235.
[50] _Zool. Garten_, 1896, p. 88.
[51] _P. Calif. Ac._ (2) v. 1895, p. 776.
[52] _Amer. Natural._ xxxiii. 1899, p. 691.
[53] _Amer. Natural._ xxxi. 1897, p. 635.
[54] _Zeitschr. wiss. Zool._ xxvii. 1877, p. 522; xli. 1891, p. 365; _Zool. Anz._ 1882, p. 513.
[55] _Zoolog. Garten._ 1896, p. 114.
[56] _Zeitschr. wiss. Zool._ xxv. 1875, p. 297. See also Hahn, _Rev. Quest. Sci._ (2), i. 1892, p. 178.
[57] _Amer. Journ. Sci._ (2), xlvi. Nov. 1868, p. 364.
[58] _Zeitschr. Biol._ xxxiv. 1896, pp. 340-396.
[59] _Zeitschr. wiss. Zool._ xxix. 1877, pp. 324 f., pl. xxii.
[60] _Ann. Mus. Genova_, xvi. 1880, p. 83.
[61] _Journ. Morphol._ viii. 1893, p. 269.
[62] _Amer. Natural._ 1891, p. 1084.
[63] _P.Z.S._ 1895, p. 150.
[64] See also M. von Chauvin, _Zeitschr. wiss. Zool._ xxxviii. 1883, p. 671.
[65] E. T. Emerson, _Proc. Boston Soc._ xxxii. 1905, p. 43.
[66] _Nature_, lx. 1899, p. 389.
[67] _Amer. Natural._ xix. 1885, p. 1226.
[68] _Proc. Ac. Philad._ 1864, p. 181.
[69] _The Natural History Review_, No. xvii. 1865, p. 97.
[70] _Journ. Ac. Nat. Hist. Philad._ vi. p. 189.
[71] Beddard, _P.Z.S._ 1895, p. 841.
[72] _Phil. Trans._ B. 136, 1896, p. 1.
[73] _P.Z.S._ 1890, p. 69.
[74] _P.Z.S._ 1894, p. 101.
[75] Groenberg und Klinckowstroem, "Zur Anatomie der _Pipa americana_," _Zool. Jahrb. Anat._ vii. 1894, p. 609.
[76] _P.Z.S._ 1896, p. 595.
[77] _Zool. Garten_, 1885, p. 299.
[78] _P.Z.S._ 1899, p. 790.
[79] _Faune Vertebr. Suisse_, iii. 1872, p. 587.
[80] _Zool. Garten_, 1885, p. 299.
[81] For further information, cf. Portschinsky, "Biologie des mouches coprophages et nécrophages, 2me partie. Étude sur la _Lucilia bufonivora_, parasite des batraciens anoures."–_Horae Soc. ent. Ross._ xxxii. pp. 225-279 (in Russian). German summary in _Zool. Centralbl._ v. 1898, pp. 855-859.
[82] _Arch. Naturg._ xliv. 1868, p. 141.
[83] _Quart. J. Micr. Sci._ xlii. 1899, p. 3.
[84] _Arbeiten Instit. Würzburg_, x. 1895, p. 57.
[85] _Proc. Bost. Soc. Nat. Hist._ xxi. 1883, p. 104.
[86] _P.Z.S._ 1895, p. 89 (with a sketch of a pond, with nests, in Dr. Goeldi's garden).
[87] _P.Z.S._ 1895, p. 209.
[88] _Arch. Anat. und Phys._ 1854, p. 449. Also Boulenger, _P.Z.S._ 1898, p. 107.
[89] _Quart. J. Micr. Sci._ xlii. 1899, p. 313.
[90] _Ann. Mag. Nat. Hist._ (5) xvii. 1886, p. 461.
[91] =_Phyllobates_ (part) Bibron; cf. Boulenger, _P.Z.S._ 1888, p. 207.
[92] See Günther, _Nature_, lii. 1895, p. 643.
[93] _Quart. Micr. Sci._ xlii. 1899, p. 329.
[94] _Arch. Naturg._ xxxiii. 1867, p. 124.
[95] _Quart. J. Micr. Sci._ xlii. 1899, p. 309.
[96] _Report on the Work of the Horn Scientific Expedition to Central Australia_, pt. ii. "Zoology," 1896, p. 164.
[97] _Proc. Linn. Soc. N.S.W._ (2), iv. 1898, p. 357.
[98] _Zool. Anz._ xvii. 1894, p. 156.
[99] _An. Soc. Espan._ i. 1822. See also Howes, _P.Z.S._ 1888, p. 231.
[100] _Quart. J. Micr. Sci._ xlii. 1899, p. 307.
[101] S. S. Flower, _P.Z.S._ 1896, p. 910.
[102] _Ibid._ p. 909.
[103] Boulenger, _Ann. Nat. Hist._ (6), iv. 1889, p. 247.
[104] See Boulenger, _P.Z.S._ 1888, p. 204.
[105] Boulenger has shown (_P.Z.S._ 1888) that Bibron's species of _Phyllobates_, hitherto grouped amongst the Cystignathidae, are Ranoids, closely allied to _Hylixalus_ and _Prostherapis_. The other species now form the Cystignathoid genus _Syrrhopus_, Cope (cf. p. 212).
[106] _P.Z.S._ 1895, p. 209.
[107] Cf. p. 273.
[108] _Zool. Jahrb. Syst._ xii. 1898, p. 89.
[109] _Monatsber. Berl. Ac._ 1875, p. 204; 1876, p. 714.
[110] _Malay Archipelago_, 2nd ed. i. 1869, p. 38.
[111] _Annotat. Zool. Jap._ i. 1897, p. 113.
[112] _P.Z.S._ 1896, p. 906.
[113] Boulenger, _Cat. Batrach. Salientia_, p. 22.
[114] _Zool. Gart._ 1885, p. 299.
[115] _Trans. Zool. Soc._ xii. 1884, p. 51.
[116] _P.Z.S._ 1884, p. 573.
[117] _British Reptiles_, 2nd ed. 1849, p. 110.
[118] Boulenger, "Tailless Batrach. of Europe," pt. ii. p. 287, _Ray Society_, 1897.
[119] Boulenger, _op. cit._ p. 278.
[120] _Phil. Trans._ clxxxvii. 1896, B. p. 23.
[121] _Anat. Anz._ xix. 1897, p. 201.
[122] _Phil. Trans._ clxxxvii. 1896, B. p. 23.
[123] _Trans. Zool. Soc._ xv.
[124] _Trans. N. Zealand Inst._ x. 1878, p. 222.
[125] _Trans. N. Zealand Inst._ xiv. 1881, p. 276; cf. also Reischek, _op. cit._ xiv. p. 274.
[126] Cope, the inventor of this most appropriate name, soon changed it, unnecessarily, into Theromora (μωρός = sluggish), perhaps in order not to emphasise too much their possible Mammalian affinities; while others rashly called them Sauro-Mammalia. For detailed illustrations of Theromorpha reference should be made to Owen, _British Fossil Reptiles_, 4to, London, 1849-55, and to numerous papers by Seeley, _Phil. Trans._ 178 (1887), 186 (1895), and by E. T. Newton in _Phil. Trans._ 184 (1893), 185 (1894).
[127] _Cat. Chelonians_, _Brit. Mus._ 1889.
[128] It should be noted that the horny pieces of the carapace are termed "shields" and the bony pieces "plates."
[129] πλευρόν, side; δειρή, neck.
[130] _Journ. Morph._ xv. 1897, p. 21.
[131] _Amer. Natural._ xxxii. 1898, p. 929.
[132] _Contributions to the Nat. Hist. of the U.S.A._, Boston, 1857.
[133] _Zool. Garten._ 189, p. 260.
[134] _Natural History of Selborne._
[135] _J. Asiat. Soc. Bengal_, vi. 1837, p. 689.
[136] Presidential Address. _Proc. Linn. Soc._ 1898. See also Günther, _Gigantic Land-Tortoises_, Brit. Mus. London, 1877; Gadow, _Trans. Zool. Soc._ xiii. 1894, p. 313; Rothschild, _Novit. Zool._, several notes.
[137] _Notes Leyden Mus._ xvi. 1895, p. 211.
[138] _Contributions to the Natural History of the U.S.A._, vol. i. 1857, p. 333.
[139] _P.Z.S._ 1875, p. 2.
[140] _Wanderings of a Naturalist in India_, Edinburgh, 1867.
[141] _Sketches of the Natural History of Ceylon_, London, 1861.
[142] _Sitzber. Ak. Berlin._ 1891, p. 115; 1893, p. 347.
[143] _J. Morphol._ v. 1891, p. 181.
[144] _J. China Asiat. Soc._ xiii. 1879, pp. 1-36, with Figs.
[145] Boulenger, _Trans. Zool. Soc._ xiv. 1898 (read Nov. 1893).
[146] νόθος = spurious.
[147] _Zool. Gart._ 1889, p. 1.
[148] _P.Z.S._ 1888, p. 351, and 1891, p. 466.
[149] _P.Z.S._ 1889, p. 602.
[150] _P.Z.S._ 1889, p. 452.
[151] F. Mason's _Burma_, London, 1882.
[152] _Sketches of the Nat. Hist. of Ceylon_, London, 1861.
[153] _P. Ac. Philad._ 1864, p. 224, and _P. Amer. Ass._ xix. 1871, p. 236.
[154] _Ann. Nat. Hist._ (5) xiv. 1884, p. 117.
[155] _Burma, its People and Productions_, London, 1882.
[156] _Zool. Garten._ 1895, p. 232.
[157] _Zool. Garten._ 1895, p. 257.
[158] _P. Linn. Soc. N.S.W._ viii. 1883, p. 300.
[159] _Tangweera_, London, 1899.
[160] _Voyage of the Beagle_, London, 1845, chap. xvii.
[161] For further anatomical details see Shufeldt, _P.Z.S._ 1890, p. 148; Boulenger, _P.Z.S._ 1891, p. 109; and Stewart, _P.Z.S._ 1891, p. 119.
[162] _P.Z.S._ 1899, p. 596.
[163] _Burma, its People and Productions_, London, 1882.
[164] _Sketches of the Nat. Hist. of Ceylon_, London, 1861.
[165] _Organic Evolution._ Translation, London, 1890.
[166] Fischer, _Zool. Garten._ 1884, p. 38.
[167] _Zool. Gart._ 1882, p. 206.
[168] _Denk. Ak. Wien._ iv. 1852.
[169] _C. R. Ass. Franc._ lxxx. 1876, No. 21.
[170] _J. de l'anat. physiol._ viii. 1872, p. 401.
[171] _Morphol. Arbeit._ vii. 1897, p. 515.
[172] _Arch. Physiol._ lxi. 1895, p. 123.
[173] Fischer, _Zool. Gart._ 1882, p. 4.
[174] For a detailed anatomical account, see West, _J. Linn. Soc._ xxv. 1895, p. 419; xxvi. 1898, p. 517; and xxviii. 1900.
[175] Clifford Allbutt's _System of Medicine_, vol. ii. London, 1896, p. 809.
[176] _Erpétologic générale, Suites à Buffon_, vol. vii. Paris, 1852.
[177] _Catalogue of Snakes, British Museum_, London, 1849.
[178] _Reptiles of British India_, Ray Society, 1864.
[179] _P. Ac. Philad._ 1864, p. 230.
[180] _Catalogue of Snakes, British Museum_, London, 1893-1896.
[181] Except _Oligodon_, _Dasypeltis_ and _Atractaspis_ (see. p. 582), in which palatal teeth are restricted to the palatines.
[182] _Atlas der Thierverbreitung_, pt. v. Gotha, 1887.
[183] W. A. Forbes, _P.Z.S._ 1881, p. 960.
[184] _Burma, its People and Productions_, London, 1882.
[185] _Rep. Brit. Ass._ 1870. _Trans._ p. 115.
[186] _P.Z.S._ 1894, p. 669.
[187] _Zool. Gart._ 1895, p. 330.
[188] _Ibid._ 1896, p. 85.
[189] The same arrangement occurs in the Colubrine genus _Polyodontophis_, with about ten species in South-Eastern Asia, Madagascar, the Comoro Islands, and in Central America.
[190] _P.Z.S._ 1896, p. 715.
[191] _P.Z.S._ 1887, p. 340.
[192] _P.Z.S._ 1887, p. 489.
[193] _Natural Science_, i. 1892, p. 44.
[194] _Verbreitung der Kreuzotter in Deutschland._ Frankfurt a. M. 1888.
[195] _J. Linn. Soc._ xxviii.