CHAPTER III. The Order of Lizards. Saurians.

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This is the second order of the great section of Scaly Reptiles (Squamata), as distinguished from the Shielded Reptiles (Cataphracta). The name Saurian, Sa????, given by Aristotle to the genus of Lizards, has been more comprehensively applied to a group of Reptiles which have the body elongated, covered with scales, or having the skin rough like shagreen. They have, for the most part, four feet, the toes of which are furnished with hooked claws; their eyelids are movable, and their jaws armed with encased teeth; they have a distinct tympanum, a heart with two auricles and a single ventricle, sometimes partially valved, having sides and a sternum. They are not subject to metamorphosis, and, finally, they are furnished with a tail.

["By far the greater number of the Saurians," writes Dr. GÜnther, "are easily distinguished from the other orders of reptiles by their elongated form, by their movable thorax covered with skin, by the presence of legs, and by their general integuments, which are either folded into scales, or granular, or tubercular, or shielded; still, there are many Saurians which, at a superficial glance, might easily be taken for members of the preceding order—that of the Snakes; and it cannot be denied that there is a gradual transition from one of these orders to the other. On the part of the Saurians, we allude to those which have no externally visible limbs, and which combine with a greatly elongate, cylindrical body, the peculiar kind of locomotion we observe in Snakes. Yet the greater affinity of these reptiles to the ordinary Lizards is indicated by another character, which is in intimate connection with their mode of life. The Snakes, having movable maxillary bones, and mandibles not joined by a symphidis, are enabled to swallow other animals of apparently greater bulk than their own. In the Saurians the maxillÆ are fixed and immovable, and the mandibles are joined by an osseous suture, so that the cleft of the mouth can be dilated only in the usual vertical direction. Moreover, in these limbless Saurians we always find bones of the shoulder hidden below the skin, whilst no trace of them can be discovered in the true Snakes. The motions of some Lizards are extremely slow, while those of others are executed, with very great, but not lasting, rapidity. Many of them have the power of changing their colours, which depends on the presence of several layers of cells loaded with different pigments; these layers the animal compresses by more or less inflating its lungs, whereby the changes in the coloration are effected."

Dr. GÜnther does not follow Dr. Gray in arranging all true reptiles into the two grand divisions of Shielded Reptiles (Cataphracta) and Scaly Reptiles (Squamata), but he includes the CrocodilidÆ among the Saurians as a first grand division of them—Emydosauri, and the other Lizards constitute his second grand division of them—Lacertini. These latter are again primarily divisible according to the structure of the tongue. Thus, in the series of Leptoglossa, the tongue is elongate, forked, and exsertile, much as in the Ophidians; in that of Pachyglossa the tongue is short, thick, attached to the gullet, and is not exsertile; and in the Vermilingues it is Worm-like, club-shaped in front, and very exsertile.

The various genera of Saurians which have either not a trace of external limbs, or have them more or less diminutive and rudimentary—either the usual two pairs or one pair only, and in the latter case sometimes the fore and sometimes the hind pair being deficient—are included among the Leptoglossa, or the series which have a forked and protrusile tongue; and, so far as is practicable, we will commence by noticing the different serpentiform genera; only, in a classification which is not confessedly superficial, it will be found that the various Snake-like Saurians appertain to several distinct natural families, most of the other genera belonging to which have, in sundry cases, limbs that are well developed. Some of them, therefore, will have to be noticed as the different families to which they belong are successively treated of; and there will yet remain the curious serpentiform family of AmphisbÆnidÆ, which Dr. Gray refers to his grand series of Shielded Reptiles (Cataphracta).

The same naturalist divides the Leptoglossa into two tribes, which he styles Geissosaura and Cyclosaura; and, as constituting particular division of the former, he includes under it the family TyphlopidÆ, which Dr. GÜnther refers—as we have seen—to the order of Ophidians. In the series of Geissosaura, the scales of the belly and (almost always) of the back and sides are quincuncial, rounded, and imbricate; the tongue is narrow, short, flat, and but slightly forked; and the head is of a conical shape, and is covered with regular shields.

Of the families thus characterised, some only have distinct eyelids, as the families AcontiadÆ, OphiomoridÆ, SepsidÆ, and ScincidÆ; while others have the eyelids rudimentary and the eyes exposed, as the families LialisidÆ, AprasiadÆ, PygopodidÆ, and GymnopthalmidÆ. In the AcontiadÆ the nostrils are placed in the enlarged rostral plate, with a longitudinal slit behind. The form of the body much resembles that of our common Orvet, or Blind-worm, and their limbs, when present, are so rudimentary that they can aid little in locomotion. One genus, Acontias, is without limbs, and the eyes are furnished with a lower lid, while the upper eyelid is rudimentary. Of this, one species, A. meleagris, inhabits South Africa; and another, A. Layardii, has been discovered in Ceylon. The genus Nessia has four rudimentary limbs, and the rostral shield is large, sub-conical, and depressed. In one species, N. monodactyla, the limbs are diminutive, the posterior placed far apart from the anterior, all being very short, weak, and undivided into toes. In another, N. Burtoni, each foot is divided into three minute toes. Both species are peculiar (so far as known) to Ceylon, and the habits of this family are much the same as those of our common Orvet (Anguis fragilis).

The family of OphiomoridÆ is founded on a single genus and species, Ophiomorus miliaris, which inhabits North Africa. As remarked by Dr. Gray, this reptile seems to be intermediate to the AcontiadÆ and the ScincidÆ, and makes it appear as if the large rostral shield of the former was formed of the united rostral, supra-nasal, and nasal shields of the present family, and of the ScincidÆ. It has an elongate, cylindrical body, without external limbs, and the ears are hidden under the skin; the eyes are distinct, with valvular eyelid; and the scales of the body and somewhat elongate tail are hexagonal.

The SepsidÆ differ from the preceding, and also from the great family of the ScincidÆ, by having the nostrils placed in the front edge of a small shield, in a notch at the hinder side of the rostral plate, which latter is rather large and square. The eyes are distinct, the lower eyelid scaly, or with a transparent disk. Body fusiform or sub-cylindrical, elongate. These reptiles burrow in dry sand, and are peculiar to the anciently-known continents and certain islands. Some have a wedge-shaped head, with prominent rostral plate. Of these the genus Sphenops has more developed limbs, each dividing into four toes; and the only species, S. sepsoides, inhabits Egypt and other parts of North Africa. Sphenocephalus has a more slender and elongate shape, and the limbs are placed more distantly apart; the anterior minute, and fitting into a groove, the posterior as large as in Sphenops, and each of them having but three toes, of which the innermost and next are sub-equal, and the outer much shorter. The only known species, S. tridactylus, is common in Afghanistan. In Scelotes the anterior limbs disappear altogether; and the only known species, S. bipes, inhabits South Africa. Other genera have a pyramidal head, with the rostral plate erect, and rounded in front. Such are the five following, each founded on a single species:—Gongylus ocellatus, from North Africa and the borders of the Mediterranean; Thyrus Bojeri, from the Mauritius; Amphiglossus astrolabi, from Madagascar; Seps tridactylus, from the south of Europe and north of Africa; and Heteromeles mauritanicus, from North Africa. The last has only two toes to the fore-feet, three to the hind; and Seps has three toes to each foot, while the other three genera have five to each foot. In general these animals are found in dry and elevated spots, where they hide themselves in the sand or under stones.

Fig. 25.—Seps tridactylus.

The ScincidÆ have the head covered with shields, which are symmetrically arranged. Tongue slender, free, extersile, terminating in two pointed lobes. Scales on the back rounded, quincuncial, imbricate; those on the belly similar to those on the back and on the sides. No fold across the throat or along the side; no femoral or inguinal pores. Tail generally long, rounded, fragile. Eyes and eyelids well developed. Nostrils in a separate plate, between the frontal and labial shields. Generally four limbs, moderately developed, sometimes feeble or hidden below the skin. The species of this family are exceedingly numerous, and inhabit almost every part of the tropical regions, some extending into the temperate zones. They are thoroughly land Lizards, preferring dry ground, and hiding themselves in the sand, under stones, fallen leaves, &c., very few of them entering the water. They do not attain to any considerable size, only a few species of Australia and the West Indies growing to the thickness of a man's wrist, and exceeding a foot in length. Some of them are viviparous, others deposit from eight to twelve globular eggs. Dr. Gray divides them into the sub-families of ScincinÆ, or those which have the scales thin, smooth, and neither striated nor keeled; the nostrils in a single smooth plate, without any lunate groove behind; and the tail round, tapering, unarmed; and TropidophorinÆ, or those which have the scales thick, bony, rugous, striated, and with one or more keels upon each of them; the rostral plate rounded in front, and the body fusiform, with well-developed limbs, which terminate always in the full complement of toes. A few species of the ScincinÆ have no external limbs, thus approximating in their appearance to certain of the burrowing Ophidians.]

The Orvet, or Blind-worm, Anguis fragilis, is small, cylindrical in shape, about eleven or twelve inches in length, and having the exterior appearance of Snakes. The scales which cover the body are small, smooth and shining, being red in the middle, and edged with white, of a silvery yellow on the upper part, and dusky beneath; the sides somewhat dusky brown, and the throat slightly marbled with white, black, and yellow. Two larger spots appear, one above the muzzle, the other upon the back of the head; from this point two blackish longitudinal rays start, which extend to the tail, as well as two other nut-brown rays, which start from the eyes; the markings vary, however, in different countries, and probably with age and sex.

The Orvet is found in woods and dry, sandy, and stony wastes. They are timid, harmless creatures, retiring into holes and concealing themselves in moss at the foot of trees to hide themselves from observation. They feed upon worms, insects, and the smaller mollusks. Although perfectly harmless, the country-people are strongly prejudiced against them, believing their bite to be a deadly poison. This animal is extremely brittle. Laurenti and others assert that when captured it throws itself into a position of such rigidity that it sometimes breaks in two, and that a smart blow of a switch will at any time divide it.

[There are little-known species of Anguis in India and South Africa, which are at least provisionally so considered, and certainly do not differ essentially; and next we come to forms in which the limbs are successively more developed. Such are the Ophiodes striatus of Brazil, which has two short, flattened, undivided, and one-pointed limbs, corresponding to the usual hind pair; the Brachymeles bonitÆ of the Philippines, in which there are two pairs of short and rudimentary limbs, the fore bearing two minute claws, while the hind are undivided; Venira bicolor, of the same archipelago has very short limbs, the fore and hind being placed distantly apart, but in this genus all have five distinct toes; Chiamelea lineata, from some part of India, and Hagria VosmaËrii, from Bengal, are kindred forms which conduct to the genus Eumeces, the species of which are very numerous, and spread over nearly all the different countries between or near the tropics, and in certain of them (as the Burmese E. anguinus) the limbs are still remarkably diminutive, and (as in E. isodactylus of Cambodia) the fore and hind limbs are placed very far apart, the body and tail being long and anguiform. In various other species of Eumeces, however, the proportions are more those of an ordinary Scink, as again in the kindred genera Mabonia and Plestiodon, which are widely distributed.

In other series of Scinks, the distinctions of which are far from being conspicuous, we again have limbless genera, or nearly so, as the Australian Soridia lineata, which has one pair of small, posterior, undivided extremities; while in another Australian form, the Rhodona punctata, the anterior pair of limbs are simple and undivided, while the hinder divide into two unequal toes, and the two pairs of limbs are situate as distantly apart. And thus we may continue to trace the successive gradations, in sundry genera, until we arrive at the Scincus officinalis of North Africa, a well-known reptile, the geographical range of which extends eastward into Afghanistan, and which was formerly in considerable request for its supposed medicinal properties. Indeed, this notion still prevails in Hindustan, into which country dried specimens of both this reptile and of Sphenocephalus tridactylus (p. 101) are brought by Afghan traders, and are sold in the bazaars. Both of these are Sand Lizards, which burrow into the sand with great rapidity.

We now come to the TropidophorinÆ, or second sub-family of Scinks indicated by Dr. Gray (vide p. 102), which have always well-developed limbs, the body only moderately elongated, and the scales variously keeled. Several species of larger size appertain to this series, as the Cyclodus gigas of Australia, and the curious Stump-tail Lizards, Trachydosaurus rugosus and T. asper, of the same insular continent, which latter have most prominently rugous scales, and the tail literally appearing like the short and abrupt stump of one. Egernia Cunninghami and Tropidolesma (of different species) are other comparatively large Australian Lizards; and examples of most of those that have been mentioned may generally be seen alive in the London Zoological Gardens, where the Cyclodus gigas has bred and proves to be viviparous. Of the species of Euprepes, of which several inhabit the Indian region, some (as the very common E. rufescens) are viviparous, and others (as E. multicarinata) are oviparous. These have three more distinct, though not prominent, keels upon each scale; and the different species inhabit both the Old World and the New, as well as Australia. The Galliwasps (Celestus) of the West Indies, and sundry other genera, do not greatly differ. Of Tropidophorus, which has exceedingly rugged scales, the species inhabit the Indo-Chinese countries, and one (T. cocinsinensis) is found likewise in the Philippines; while of another (T. Berdmorei), in Burmah, Mr. Theobald remarks that "its scales are dull and lustreless, and the coloration peculiar for a Scink. It harbours under half-immersed stones, and enters the water and gravel freely." In several of this family of Lizards the scales are beautifully iridescent, and many of them show longitudinal pale or white lines, or are otherwise variegated.

Nearly akin to the extensive family of ScincidÆ, there are three small families (as classed by Dr. Gray), the species of which are peculiar to Australia. They have small, undivided, posterior limbs only, or are quite limbless. These families are the LialisidÆ, founded on three or more species of a single genus, Lialis; the AprasiadÆ, founded upon one species only—Aprasia pulchella, which is limbless; and the PygopodidÆ, comprising the two genera Pygopus and Delma, the former containing two, the latter only one ascertained species. The GymnopthalmidÆ constitute still another small family, quadrupedal, but with the limbs small and weak. Of seven genera referred to it, five are Australian, one is European, and one belongs to South America. Ablepharus pannonicus is a small Lizard of this family, inhabiting Eastern Europe, with a congener, A. bivittatus, in the Caucasus; and Gymnopthalmus lineatus inhabits Brazil and the Island of Martinique.

In the second tribe of Leptoglossa, entitled Cyclosaura, the scales of the belly are square, in cross bands; those of the back and tail are rhombic and imbricate, or circular and subgranular; the tongue is lengthened, and more or less conspicuously furcate; and the eyes are diurnal, having two valvular lids. The limbs are generally well developed; but in several genera they still are more or less rudimentary, or even absent.

There are four small families in which the sides are rounded and covered with scales like the back. Of these, that of ChamÆsauridae is founded upon the South African Lacerta anguina of LinnÆus, now ChamÆsaura anguina, which has the limbs quite rudimentary. In the American families of CercosauridÆ, ChirocolidÆ, and AnadiadÆ, the limbs are moderately developed, and have each five toes. The two last-mentioned families are founded each upon a single species, Chirocolus imbricatus and Anadia ocellata; and the other contains the two genera Circosaura and Lepisoma—of which the first comprises some two or three species only. All of these reptiles have exceedingly long tails, though not so inordinately long as in the LacertidÆ of the genus Tachydromus.

Certain other families have a distinct longitudinal fold, covered with small granular scales on each side. These are the families ChalcidÆ, HolaspidÆ, and the more extensive one of ZonuridÆ. The ChalcidÆ have the head covered with regular many-sided shields, and the lateral fold is indistinct; limbs small and rudimentary, and the hind feet are undivided in the genera Chalcis and Bachia, with three tubercles in place of toes in Microdactylus, and with four clawed toes in Brachypus. Each of these genera is founded on a single species, and all are doubtless peculiar to the New World. The HolaspidÆ is also founded on one species only, the Holaspis Guentheri, which again is supposed to be South American. It has four well-developed limbs, a double row of plates along the back and upper surface of the tail, and the latter organ is curiously serrated laterally.

The ZonuridÆ constitute a considerable family, to which some eighteen or twenty genera are assigned, and which present considerable modification of form. The ears are distinct, whereas in the ChalcidÆ they are hidden under the skin. The head is pyramidal, or depressed, and covered with regular many-sided shields; eyes with two valvular lids. Limbs mostly well developed, but short in some, and rudimentary, or even wanting in the so-called "Glass-snakes" which constitute the sub-family PseudopodinÆ. There is no external trace of them in the North American Glass-snake, Ophisaurus ventralis; and in the Old World genus, Pseudopus, there is only one pair, posterior, rudimentary, and undivided. These reptiles are long, and serpentiform in shape: whilst in other Saurians the whole skin of the belly and of the sides is extensible, the extensibility is limited in the "Glass-snakes" to a separate part of the skin; and, as Dr. GÜnther remarks, "the scaly covering of the upper and lower parts is so tight that it does not admit of the same extension as in Snakes and other Lizards; and the Pseudopus, therefore, could not receive the same quantity of food in its stomach as those animals, were it not for the expansible fold of the skin running along each side of its trunk." One species of Pseudopus, the P. Pallasii, inhabits Asia Minor and the south-east of Europe; and there is another, P. gracilis, in the Indo-Chinese countries (or those lying eastward of the Bay of Bengal). A second sub-family, GerrhonotinÆ, is peculiar to America, and consists of more ordinarily-shaped Lizards, which are ranged in four genera. Together with the Ophisaurus, or American Glass-snake, they are the only known ZonuridÆ that inhabit the New World. The great mass of this family and all of its most characteristic species are African, and these are arranged by Dr. Gray under the sub-families CicigninÆ and ZonurinÆ. In the first of these sub-families the tail is smooth, or unarmed, and in the second it is spinous. The Cordules, Cordylus, Zonurus, &c., are very characteristic Lizards chiefly of Southern Africa, several species of which have been figured by Sir Andrew Smith. They are mostly of shortish form, and the neck is more or less spinous; the body-scales in some (as Zonurus cataphractus) being extraordinarily rugous. These Lizards squeeze themselves into crevices in the rocks, in which they hold on so firmly by their nuchal spines that it is next to impossible to dislodge them, the tail commonly giving way at once if it be attempted to pull them forth by means of it.

The family of LacertidÆ, comprising our ordinary European Lizards, have no longitudinal fold along the sides, but generally one across the throat; the tail is very long, rounded, with its scales arranged in rings, being also fragile; the head is covered with shields, which are symmetrically arranged; scales on the back granular or rhombic; on the sides granular; on the belly largely quadrangular or rounded, and arranged in cross-bands; eyes diurnal, with eyelids; the tympanum distinct; limbs always four, and well developed. This group of Lizards has no representative in America or (so far as known) in Australia.

The sub-family of TachydrominÆ is included by Dr. Gray in the family ZonuridÆ. These are Asiatic Lizards, with a most inordinate length of tail, the fore and hind limbs being not placed distantly apart, as in the various anguiform Lizards already treated of—there is an indistinct collar, and the toes are not serrated or keeled. Two genera have been distinguished, Tachydromus and Tachysaurus, the latter founded on a Japanese Lizard, T. japonicus. At least three species are known of Tachydromus, two of which inhabit China, T. septentrionalis and T. meridionalis; the third belonging to the Indo-Chinese countries, T. sex-lineatus. In an example of the last, measuring fourteen inches long, the tail occupies eleven inches and a half. It is the longest-tailed creature that we have any knowledge of, in proportion to its other parts; indeed, something quite wonderful to behold and muse over.

The rest of the LacertidÆ are chiefly from Africa and the south of Europe; there are probably more of them to be discovered in Middle Asia, and only three or four species are known to inhabit the Indian region. Fifteen or more genera are recognised. In temperate Europe (inclusive of the British Islands) two species are common—the Zootica vivipara and the Lacerta agilis. The former, as its name imports, is viviparous, whereas the other genera belonging to the family are (so far as known) oviparous. Others occur in the south of Europe.]

The common Grey or Sand Lizard (L. agilis), sometimes attains the length of from eight to ten inches, of which the tail occupies more than half. These little inoffensive creatures, so common in Southern Europe, are slender and active; their movements are so rapid that they escape the eye as quickly as a bird. They require a mild temperature, and seek shelter among ruins. When the sun strikes with its meridian force upon a wall, they may be seen basking in its rays, enjoying themselves delightedly upon the heated surface. They seem to be pervaded with the blessed warmth, and mark their pleasure by soft undulations of the tail. It is commonly said that the Lizard is the friend of Man, since far from flying at his approach, they seem to regard his appearance with great complacency. They pass the winter at the bottom of small holes which they have hollowed out of the earth, where they become torpid. At the commencement of spring they issue from their hiding-place, and each seeks its mate; they go in pairs, male and female, it is said, living in faithful union for many years, sharing between them the domestic arrangements, which comprise hatching the young and nursing them in their helplessness, carrying them into warm and sunny places, and sheltering them from cold and damp.

Lizards feed chiefly upon insects, and especially flies. All who have watched the actions of the Grey Lizards must have observed that the caudal vertebrÆ are so extremely fragile that they separate on the slightest touch, the tail remaining in the hand of any one attempting to seize it. These tails sometimes grow again. When an attempt is made to seize a Grey Lizard on the wall it lets itself fall to the ground, and remains there a moment immovable before attempting to run, evidently simulating death.

Grey Lizards are easily tamed, and appear happy in captivity. From their extreme gentleness they soon become familiar with their keepers, and return caress for caress, approaching mouth to mouth, and suck the saliva from between their lips with a grace that few people would allow them to display.

In the Green Lizard, L. viridis, the scales of the temple are many-sided and unequal, with a central layer; back granular and oblong, with shelving sides; throat fold distinct. Nothing can be more brilliant than the variegated colouring with which it is ornamented. Its favourite locality is a slightly elevated woody place, where the sun's rays readily penetrate. It is also found in sunny meadows. It feeds upon small insects, and shows no alarm at the presence of Man, but stops to look at him. Snakes, on the contrary, they seem to fear much, but when they cannot avoid them they fight courageously. In length they are about eighteen inches.

Green Lizards are found in Jersey and Guernsey, and other warm countries of Europe, on the African coast of the Mediterranean, and they are not rare in France.

How often have we admired their magnificent colours in the neighbourhood of Montpelier, where they rival the green of the meadows, and glitter in the sun like so many living emeralds!

In the Ocellated Lizard, L. ocellata, the upper part of the body is green, variegated, spotted, and reticulated or ocellated with black, having large round blue spots upon the flanks; the underpart of the body is white, frosted with green; in size it is about twenty inches. They are found at Fontainebleau, in the south of France, and in Spain. They establish themselves in hard sand, often between two beds of calcareous rock, upon some steep declivity, more or less directly exposed to the south; they are also found between the roots of old stems, either in hedgerows or vineyards. They feed almost exclusively on insects; but are said to attack Mice, Shrews, Frogs, and even Snakes, and to destroy the eggs of the Partridge. They have sometimes been tamed by feeding them on milk.

[In the genus Ophiops, two species of which inhabit Asia Minor, and one of them the shores of the Mediterranean, the eyelid is rudimentary and the eye exposed, whence the name, signifying "snake eye." So far as known, the habits of the various Lizards which constitute the family of LacertidÆ are much the same.

The family of TeidÆ is peculiar to the New World, and some of the species attain to the length of several feet. In these Lizards the head is pyramidal, and is covered with regular many-sided shields; supra-orbital plate horny; the teeth solid and well rooted; tongue elongate, flat, free (rarely slightly sheathed at its base); the scales of the back are regular and keeled, and of a rhombic shape; sides flat, and covered with small granular scales; the throat scaly, with a double collar, rarely indistinct.

In some the throat has two cross-folds, with large six-sided scales within; and of these some have the ventral shields small, long, and smooth, while others have them much broader. The former are known as the Teguexins (Teius and Callopistes), and the latter as the Ameivas (Ameiva, and three other genera). One species of Teguexin, Teius teguexin, may commonly be seen alive in the London Zoological Gardens. This is a large and powerful Lizard, exceeding five feet in length when full grown, and extremely active. It feeds on small living animals of any kind, and will even devour poultry, and especially their eggs, for which latter it manifests an especial liking, as observed in captivity. Sometimes it has been known to prey on other and kindred Lizards, as the Ameivas. The teeth of this species are strong, and the reptile can bite with great force. It is a bold and determined combatant when attacked, and if it succeeds in seizing its foe, retains its hold with pertinacity. Its flesh is eaten by some people, who consider it excellent. Together with a second species, T. nigropunctatus, it inhabits Brazil, and the two species of Callopistes are also South American, one at least of them occurring in Chili. The species of this family, although strong and agile, never ascend trees, but range at will the hot sandy plains or the dense and damp underwood on the margins of lakes and rivers, into which they plunge when alarmed, and remain below the surface until the danger has passed away, their capacious lungs and imperfect circulation permitting them to endure a very long immersion without inconvenience.

The Ameivas have a long whip-like tail, and peculiarly elongated toes on their hind feet. The species of Ameiva and Cnemidophorus are numerous, and the genera Dicrodon and Acrantus are founded each of them upon a single species. In general these are Lizards which correspond with the ordinary LacertidÆ of the Old World. One species only, Cnemidophorus sex-lineatus, inhabits the Southern States of North America; there are at least four others in Mexico, and the rest belong to South America and the Antilles. "The Ameiva dorsalis," writes Mr. Gosse, "is one of the most common of the reptiles of Jamaica, and is as beautiful as abundant. Its colours are striking, but not showy, and its countenance has a very meek expression. All its motions are elegant and sprightly; when it is proceeding deliberately, its body is thrown into latent curves the most graceful imaginable; but when alarmed its swiftness is so excessive that it appears as if it literally flew over the ground, and the observer can scarcely persuade himself that it is not a bird. It is very timid, and though its toes are not formed as in the Geckos and Anoles, for holding on against gravity, I have seen a large Ameiva run with facility on the side of a dry wall, along the perpendicular surfaces of the large stones."

A second series occurs in those TeidÆ which have a collar of large shields on the throat. As many as five genera of them have been established, each upon a single species, and all are from intertropical America. In Crocodilurus lacertinus the two rows of crests along the tail recall to mind the Crocodiles, whence the name bestowed. Others have been styled Dragons, as the Great Dragon, Ada guianensis, and the Smaller Dragon, Custa bicarinata. All bear a certain amount of superficial resemblance to the Crocodiles, and the Great Dragon grows to six feet in length, and is found in many parts of South America. This large reptile runs up the trunks of trees with facility, is quick when on the ground, and it also swims, though not particularly well. It preys upon such small animals as it can manage to seize, and chiefly frequents the inundated savannahs and marshy localities, where it is seen basking in the sunshine; but there is considerable difficulty in taking this Lizard, as it makes generally for its burrow in some raised spot, and bites desperately in self-defence. Its flesh is eaten, and is considered a delicacy. Its eggs, also, are considerably esteemed at Cayenne and other places, and each female lays some dozens of them.

The family of HelodermidÆ is founded on a very remarkable Lizard from Mexico, the H. horridum, which is of the same size as the Great Dragon, and in some respects approximates the following Old World family of VaranidÆ. Its back and sides are covered with oblong, hexagonal, very convex and shield-like scales, and the belly with oblong, rather convex plates; tail cylindrical, with oblong, convex scales above, and flat, elongate, thin plates beneath. The head is somewhat flattened, and is covered with polygonal, convex shields; the muzzle is rounded; and the teeth are on the inner side of the jaws, incurved, with a groove on the front of their inner side. The bite of this reptile is said to be severe.

The family of VaranidÆ inhabit South-eastern Asia and its islands, Africa, and Australia. In this family are comprised the largest of existing Lizards, with the exception of the CrocodilidÆ. They are very commonly miscalled Iguanas by Europeans and their descendants, in the countries where they are found. These reptiles have a pyramid-shaped head, more or less elongated, and covered with small and scale-like, but not imbricate, shields. Their teeth are acute and compressed. The tongue is elongate, slender, terminating in a long fork, and is retractile into a sheath at its base. Their scales are small, equal on the sides and on the back, and arranged in cross rings; those on the belly and tail are square, in cross bands. Tail long, and generally more or less compressed. The feet are well developed, with five toes on each, which are armed with strong claws. Most of them live near water, and they are excellent swimmers, their long and compressed tail serving as a propeller. Their movements on land are not much less rapid than in the water. Several of the species climb trees, and they are more or less nocturnal in their time of action, though also about by day. They are exclusively carnivorous, feeding on the different water animals, and on the eggs of birds, and likewise on those of other large reptiles; some of them are also destructive to ducklings, and to various Snakes. Dr. GÜnther remarks that "their external nasal opening leads into a spacious cavity situated in the snout; when the animal dives, it closes the nasal aperture, and retaining a certain quantity of air in that pouch, or rather in the two pouches, it is enabled to remain under water for a prolonged period without the necessity of rising to the surface in order to breathe. It is the same plan of structure as that with which a large northern Seal (Cystophora borealis) is provided." In like manner, the air-bag connected with the one developed lung of the Ophidians retains the necessary supply of air during the tedious process of deglutition or swallowing. The nostrils are variously placed, either mid-way between the eye and muzzle, or nearer to one or to the other; and according to this and some other differences, Dr. Gray divides the VaranidÆ into as many as seven genera, but Dr. GÜnther would seem to admit not more than two genera. When the tail of these Lizards is mutilated, the lost portion is never renewed; whereas in the preceding families of the ZonuridÆ, LacertidÆ, and TeidÆ a new tail or portion of one soon sprouts forth—but this renewed portion contains no bony vertebrÆ, and it remains smooth externally; when the fracture is cleft, as sometimes happens, two new tails are put forth. Another family of Lizards in which the tail is thus commonly renewed is that of the Geckos; but never in the IguanidÆ, the AgamidÆ, and the ChameleonidÆ, any more than in the VaranidÆ. The species of this family defend themselves vigorously, when attacked, by lashing forth smart blows with the tail, as do also the Crocodiles and the larger IguanidÆ.

In the genus Varanus, the nasal apertures form an oblique slit, in, or nearly in, the middle, between the eye and the tip of the snout. The scales are elliptic and small; those on the back and on the sides are not imbricate, each of them being surrounded by a small, circular, granular fold. Tail with a low crest, formed by two or four series of strongly keeled scales. Throat with a transverse fold. One very common in India and Ceylon is the V. dracÆna, which grows to a length of five feet, the tail being longer than the body. These reptiles live in holes, and in mid-day they steal out of their cells to seek their food, which consists chiefly of the smaller reptiles and of insects. In many parts of India, and in Ceylon, the flesh is much eaten by the natives. The late Dr. Kelaart states that he once tried some excellent soup made from it, which tasted not unlike hare-soup. At Trincomali, he tells us, they are hunted down by Dogs, and sold in the market for sixpence each. This species climbs walls, and holds on so firmly with its strong claws, wherever these can be inserted, that it is actually used by house-breakers in India to help in raising themselves up a wall or building, the man grasping the tail, while the reptile affords a lift by endeavouring to escape from him upwards. It lays twenty or thirty eggs, which in texture and appearance resemble those of many Snakes, being similarly agglutinated together by a viscid mucus. Sir J. E. Tennent remarks that "one of the earliest, if not the first, remarkable animal to startle a stranger on arriving in Ceylon, whilst wending his way from Point de Galle to Colombo, is this large Lizard, which may be seen at noonday searching for Ants and other insects in the midst of the highway and along the fences. When disturbed, but by no means alarmed, by the approach of Man, it moves off to a safe distance; and the intrusion being at an end, it returns again to the occupation in which it had been interrupted. It lives in any convenient hollow, such as a hole in the ground, or the deserted nests of the Termites; and some small ones, which frequented my garden at Colombo, made their retreat in the heart of a decayed tree."

Of another species, V. flavescens, which inhabits Lower Bengal, and to the eastward in Burmah, &c., Mr. Theobald remarks that "large specimens are not often procurable by Europeans, as they are much sought after by both Burmese and KarÉns as choice articles of food. They are chiefly hunted with Dogs, whose scent enables them to discover the Varans in the hollow trees in which they habitually shelter themselves. A Burman, though ordinarily a lazy man, will think nothing of cutting down and breaking up a large tree in which one of these creatures has sought refuge. The VaranidÆ deposit their eggs in the ground, usually selecting a deserted White-ant's nest. The eggs are cylindrical, with tapering ends, of a dirty white colour and leathery texture (those of V. dracÆna are two inches long), and, being esteemed an uncommon luxury by the Burmese, sell dearer than fowls' eggs. They are oily and feculent-looking, though devoid of any nauseous odour, and some Europeans eat them with pleasure."

A well-known African species, the V. or Psammosaurus scincus, extends (without the slightest difference) to the extreme desert region of the north-west of India, and more habitually frequents dry localities than others. In this species the nasal apertures are placed very near the eyes.

In the genus Hydrosaurus, the nostrils are more or less rounded, and are situate near the extremity of the snout. These animals are more decidedly aquatic than the preceding, and some of the species grow to seven or even eight feet in length. Such is the H. giganteus of Australia, where three, if not four, species inhabit. In all south-eastern Asia and its islands, its range extending to Lower Bengal but not to India proper, although found in Ceylon, the H. salvator is a common species, which, according to the late Dr. Cantor, is "very numerous in hilly and marshy localities of the Malayan peninsula. It is commonly, during the day, observed in the branches of trees overhanging rivers, preying upon birds and their eggs and smaller Lizards, and when disturbed it throws itself from a considerable height into the water; it will courageously defend itself with teeth and claws, and by blows with its tail."

We have now to treat of the

Pachyglossa,

Which are those Lizards which have the tongue short, thick, attached to the gullet, and not exsertile. These fall under two very distinct tribes—the Strobilosaura and Nyctisaura of Dr. Gray, or the tribe of the Iguanas and their kindred, and that of the Geckos and their kindred. The tribe of

Strobilosaura

Have the scales of the back and sides imbricate, generally rhombic, and those of the lower parts imbricate and of small size. Tail with more or less distinct whorls of scales. The eyes diurnal, with round pupil, and valvular lids. Feet with toes of very unequal length. Many of these reptiles have a row of spines or spine-like scales along the back and tail, which in some are very long, while others have high dorsal and caudal crests, an expansile gular pouch, or other adornments. Like the Varans among the Leptoglossa (p. 114), these Lizards do not renew the tail, or a portion of it, after mutilation. There are two great families of them—one peculiar to the Old World with Australia, the other to the New World; but as families they do not differ much, and might very well be retained as divisions of the same extensive family.

In the family of IguanidÆ, all of which inhabit America or its islands, the teeth are round at the root, dilated and compressed at the tip, and toothed at the edge; they are placed in a simple series on the inner side of the jaws, just below the edge, and are covered on the inner side by the gums; as they fall out they are replaced by others, which grow at the base of their predecessors, and gradually cause the absorption of their roots. Probably not fewer than a hundred and fifty species are now recognised, which are distributed under more than fifty genera. We can only notice a few of the most remarkable of these Lizards, some of the larger of which attain a length of five or six feet, with proportionate bulk of body. As a general rule, the larger species are mainly herbivorous, while the smaller are chiefly insectivorous, though many of the latter also devour fruit. As most of them are remarkable for their rapid changes of colouring, the name of Chameleon is often misapplied to them, in the supposition that the Chameleons are the only Lizards in which that curious phenomenon is observable. In one remarkable species, the SphÆrops anomalus, inhabiting Brazil, it is stated that the eye nearly resembles that of the true Chameleons, and it is also one of those which are particularly celebrated for its changes of hue.]

The name Iguana was given by Laurenti to a heterogeneous group of Saurians, various forms being included which were first separated by Daudin. The Iguanas, as thus restricted, are characterized by a very large thin dew-lap under the neck, a double row of small palatal teeth, and a crest on the back and tail; the latter long, slender, compressed, and covered with small imbricated and carinated scales. Messrs. DumÉril and Bibron describe the genus, thus modified, as principally remarkable for the cutaneous prolongation which constitutes the deep and thin dew-lap, or pouch, the free border of which describes a curved line, and is dentated at the part nearest the chin. The head is moderately long, and has the form of a pyramid with four faces. The neck is slightly compressed, the limbs long, the toes unequal and sometimes denticulate on the edge. The five toes of the posterior feet are graduated; the tail, which is long and slender, is slightly flattened from right to left. The Iguanas live chiefly on trees, but they take readily to the water, swimming with great facility.

There are numerous species, all of which are found in South America and the Antilles. In the Island of Isabella, Sir E. Belcher found swarms of them which he had reason to consider omnivorous, feeding voraciously on birds' eggs and the intestines of birds and insects.

The Common Iguana, I. tuberculata, which inhabits a great part of South America, is one of the best known species of this family. These reptiles are easily recognised from the large pouch underneath the neck, and the dentated crest which extends from the head to the extremity of the tail. The tail, feet, and body are covered with small scales. On the upper part, their colour is a more or less decided green, sometimes becoming blue, at others slate-coloured; the lower part is of a yellowish green. The sides present zigzag, roundish, brown scales, edged with yellow; frequently a yellow line is traced obliquely in front of the shoulder, and some individuals are sprinkled with brown; others have the limbs spotted with brown on a black ground. The tail is surrounded with brownish rays alternating with others green and yellow. When full grown it attains the length of four feet, but the more ordinary length of the animals is about thirty inches. They are very gentle creatures, and perfectly harmless, feeding almost exclusively on vegetables. They are hunted in America for their flesh, which is excellent; and they are especially common at Surinam, in the neighbourhood of Cayenne, and in Brazil.

[Of a kindred species, Metopoceros cornutus, which also is common in the Antilles, an excellent description has been published by Lieutenant Tyler,22 which we must endeavour to condense. This reptile attains a length of five, and sometimes even of six feet, the tail being about twice and three quarters the length of the body. When first hatched it measures four inches. The mouth is large, and is armed with two rows of maxillary and two of palatal teeth, which appear simply to be intended to crop leaves and to provide the stomach with vegetable food. Each maxillary tooth is a little double-edged saw, and they are so lapped over each other that the reptile, in closing its mouth upon a leaf, cuts through it completely. The tongue is curiously used by the animal to draw food into the mouth, and to forward it down the gullet, or to repel it at will, and the only use of the palatal teeth appears to be to secure the food while the tongue moves forward to afford fresh assistance in its journey down the throat. The tongue is always covered by a glutinous secretion, which is perceptibly appended to the jaws when the mouth is open. Between the lower jaw and the chest is a pouch, which the animal draws in or extends simultaneously with the compression or swelling out of the body when enraged or excited. The portion of the gular pouch attached to the jaw is inflatable, and food is sometimes retained in it for a considerable period, but the lower part is merely extensible.

"Whilst always retaining the same colours, this Iguana has the power of considerably changing its hues; but these changes are gradually performed. The colours become more dull as the period of the change of cuticle approaches—which is not, however, very frequent. Each scale has its own tint, and the colours being thus irregularly blended, an appearance is given, particularly to the younger reptiles, very much like that of worsted-work.

"These Iguanas live principally on trees, and near the windward coast of the island" (of St. Lucia). "They are not much seen, excepting in the months of February, March, and April, when they quit their hiding-places, and repair to the sea-shore or other sandy places to lay their eggs in the sand. The older females lay a great number of eggs. I have known an instance of one in confinement laying five in one day, and thirty-two within the space of ten minutes five days afterwards, making thirty-seven in all. Younger females are much less prolific, according to their size. The eggs are very liable to destruction by Ants, which fact probably accounts for their being usually deposited in sea-sand. They are soft, and without any white, and their shell resembles the most beautiful kid leather used for French gloves, of a very light straw-colour. They are about the size of those of a domestic Pigeon, but rather longer; but they vary in dimensions according to the age and size of the Iguana.

"This Iguana is not averse to water, when not too cold, taking to it only when the sun is shining; in fact, not moving about much at any other time. Its mode of swimming differs from that of other Lizards, inasmuch as it places its four legs close by the side of its body, and swims entirely with its tail. It dives with great facility, and remains sometimes for a considerable time under water. I believe that it never ventures into the sea. The tail is a very valuable limb; for, besides being the sole means of swimming possessed by the animal, it is of great use in climbing trees, although not prehensile; and it is a most important weapon of defence, a blow from it being frequently sufficient to inflict a severe wound. In fact, this reptile is rather formidable when brought to bay in the woods. It is hunted by the natives with Dogs trained for the purpose. The Dog, immediately upon scenting it, gives tongue, and, if on the ground, the Dog seizes it by the back, and either kills it or maims it, which makes its capture easy; if in a tree, the Iguana is either shaken down—a matter ordinarily of no small difficulty—or the branch is cut off. It is almost useless to attempt to find these reptiles without Dogs, as the resemblance of their colour to that of the trees which they inhabit prevents them from being easily seen. Few Dogs but those accustomed to the sport will touch them, as, in addition to the blows which they inflict with the tail, they bite and scratch furiously; and when once they lay hold of anything with their teeth, they can only be made to let go by an inducement to bite some other attractive object being offered to them. They run into holes when chased, if an opportunity offers, and when their eyes are hidden from view, they fancy that their whole body is safely covered. The flesh, particularly of the female, is a great delicacy; it is cooked in various ways, sometimes in a fricassee, with the eggs whole, sometimes roasted or stewed. The eggs have a very glutinous consistence. The flesh is said to disagree with some constitutions.

"Unless when caught young, it is very difficult to induce these reptiles to feed in confinement, and particularly when watched. Their disposition is sulky and savage, and I have known some of them," continues Lieutenant Tyler, "to die in confinement from starvation, rather than feed. This has caused me to try the following plan, which I find very successful, of affording them nourishment:—I hold them by the lower part of the body with one hand, and with the other I irritate them until they open their mouth and attempt to bite, when I insert food; and by annoying them in this way, I have not only made them eat their natural food, but I have killed some of them by forcing them to eat corn and leaves, which appear to have disagreed with them. By some of the natives this Iguana is said to eat Lizards and insects; but I have opened several, and I have never succeeded in finding any but vegetable matter in the stomach."

Of the habits of a kindred species of Iguana, the Cyclura lophura, inhabiting Jamaica, Mr. Gosse has given an elaborate description; and he tells us that the gular pouch in the IguanidÆ "is extensible, but not inflatable," as is the current opinion. Holbrook and others have remarked the same; and Professor Thomas Bell describes the fold of skin as being drawn down by a peculiar arrangement of the lingual bone, and a singular cartilage fixed to it and attached also to the skin. These parts are moved by delicate muscles, so that, when the cartilage is drawn down, the skin of course is distended, and follows it "in the same way that the silk is stretched over the whalebone of an umbrella." "In fact the skin," writes Professor Holbrook, "when distended in life by the animal, does not resemble the inflated vocal sacs of the Frogs and Toads, which are round, but looks like a fold of the skin, pinched and drawn down, the two portions of it being in contact, like a dew-lap." It appears that the Cyclura, also, is exclusively herbivorous; and Mr. Gosse remarks upon the severe wounds which it inflicts upon Dogs with its sharply-serrated tail. In general, the larger species of this family are solely vegetable-feeders, while the smaller kinds (such as the Anoles) are more or less insectivorous; and there are some, of intermediate size, which even prey occasionally upon the kindred Anoles and other small animals. The genera of these reptiles are exceedingly numerous, as we have seen, and amongst so many there must be considerable variety in the habits; but we can only notice a very few of them. Within the limited area of the small archipelago of the Gallapagos, situated on the equator about ten degrees west of South America, there are two remarkable species of IguanidÆ, of which the habits have been described and commented upon by Mr. Darwin in his volume of the "Voyage of H.M.S. Beagle." One of them is particularly so, because, as that naturalist observes, it is the only existing Saurian which can properly be said to be a maritime animal. In the whole of that group of islands, as he tells us, there is only one rill of fresh water that reaches the coast; yet this reptile frequents the sea-beaches, and no other parts of the islands. He adds that it is the only known existing Lizard that feeds exclusively on aquatic productions. Although he refers both species to the genus Amblyrhynchus, the aquatic sort now constitutes the genus Oreocephalus of Dr. Gray, and it bears the name of O. cristatus. This Lizard, according to Mr. Darwin, "is extremely common on all the islands throughout the archipelago of the Gallapagos. It lives exclusively on the rocky sea-beaches, and is never found—at least, I never saw one—even ten yards inshore. It is a hideous-looking creature, of a dirty black colour, stupid and sluggish in its movements. The usual length of a full-grown one is about a yard, but there are some even four feet long. I have seen a large one which weighed twenty pounds. On the island of Albemarle they seem to grow to a greater size than on any other. These Lizards were occasionally seen some hundred yards from the shore swimming about; and Captain Colnett, in his 'Voyage,' says, 'they go out to sea in shoals to fish.' With respect to the object, I believe that he is mistaken; but the fact stated on so good an authority cannot be doubted. When in the water the animal swims with perfect ease and quickness, by a serpentine movement of its body and flattened tail—the legs, during this time, being motionless and closely collapsed on its sides. A seaman on board sank one, with a heavy weight attached to it, thinking thus to kill it directly; but when an hour afterwards he drew up the line, the Lizard was quite active. Their limbs and strong claws are admirably adapted for crawling over the rugged and fissured masses of lava which everywhere there form the coast. In such situations, a group of six or seven of these ugly reptiles may oftentimes be seen on the black rocks, a few feet above the surf, basking in the sun with outstretched legs. I opened the stomachs of several," continues Mr. Darwin, "and in each case found it largely distended with minced sea-weed of that kind which grows in thin foliaceous expansions of a bright green or dull red colour. I do not recollect having observed this sea-weed in any quantity on the tidal rocks; and I have reason to believe that it grows at the bottom of the sea, at some little distance from the coast. If such is the case, the object of these animals occasionally going out to sea is explained. The stomach contained nothing but the sea-weed. Mr. Bynoe, however, found a piece of a Crab in one; but this might have got in accidentally. The intestines were large, as in other herbivorous animals."

The food of this Lizard, equally with its compressed form of tail, and the certain fact of its having been seen voluntarily swimming out at sea, absolutely prove its aquatic habits; nevertheless, as we are told by Mr. Darwin, "there is in this respect one strange anomaly, namely, that when frightened it will not enter the water. From this cause, it is easy to drive these Lizards down to any little point overhanging the sea, where they will sooner allow a person to catch hold of their tail than jump into the water. They do not seem to have any notion of biting; but when much frightened they squirt a drop of fluid from each nostril. One day I carried one to a deep pool left by the retiring tide, and threw it in several times as far as I was able. It invariably returned in a direct line to the spot where I stood. It swam near the bottom, with a very graceful and rapid movement, and occasionally aided itself over the uneven ground with its feet. As soon as it arrived near the margin, but still being under water, it either tried to conceal itself in the tufts of sea-weed, or it entered some crevice. When it thought the danger was passed, it crawled out on the dry rocks, and shuffled away as quickly as it could. I several times caught this same Lizard by driving it down to a point, and though possessed of such perfect powers of diving and swimming, nothing would induce it to enter the water; and as often as I threw it in, it returned in the manner above described. Perhaps this singular piece of apparent stupidity may be accounted for by the circumstance that this reptile has no enemy whatever on shore, whereas at sea it must often fall a prey to the numerous Sharks. Hence, probably urged by a fixed and hereditary instinct that the shore is its place of safety, whatever the emergency may be, it there takes refuge. I asked several of the inhabitants if they knew where it laid its eggs: they said, that although well acquainted with the eggs of the other kind, they had not the least knowledge of the manner in which this species is propagated—a fact, considering how common an animal this Lizard is, not a little extraordinary. During our visit (in October) I saw extremely few small individuals of this species, and none I should think under a year old. From this circumstance it seems probable that the breeding season had not commenced."

The terrene species, Amblycephalus subcristatus, unlike the aquatic one, is confined to the central islands of the Gallapagos archipelago, where they inhabit both the higher and damp, as well as the lower and sterile parts; but in the latter they are much more numerous. "I cannot give a more forcible proof of their numbers," relates Mr. Darwin, "than by stating that, when we were left at James Island, we could not for some time find a spot free from their burrows on which to pitch our tent. These Lizards, like their brothers of the sea-kind, are ugly animals; and, from their low facial angle, have a singularly stupid appearance. In size, perhaps, they are a little inferior to the latter, but several of them weighed between ten and fifteen pounds each. The colour of their belly, front legs, and head (excepting the crown, which is nearly white) is a dirty yellowish orange; the back is of a brownish red, which, in the younger specimens, is darker. In their movements they are lazy and half-torpid. When not frightened, they slowly crawl along, with their tails and bellies dragging on the ground. They often stop and doze for a moment, with closed eyes, and hind legs spread out on the parched soil. These Lizards inhabit burrows; which they sometimes excavate between fragments of lava, but more generally on level patches of soft volcanic sandstone. The holes do not appear to be very deep, and they enter the ground at a small angle; so that when walking over one of these Lizard warrens, the soil is constantly giving way, much to the annoyance of the tired pedestrian. This animal, when excavating its burrows, alternately works the opposite sides of its body. One front leg for a short times scratches up the soil, and throws it towards the hind foot, which is well placed so as to heave it beyond the mouth of the hole. This side of the body being tired, the other takes up the task, and so alternately. I watched one for a long time," continues Mr. Darwin, "till half of its body was buried; I then walked up and pulled it by the tail; at this it was greatly astonished, and soon shuffled up to see what was the matter; and then stared me in the face, as much as to say, 'What made you pull my tail?' They feed by day, and do not wander far from their burrows; and, if frightened, they rush to them with a most awkward gait. Except when running downhill, they cannot move very fast; which appears chiefly owing to the lateral position of their legs. They are not at all timorous; when attentively watching any one, they curl up their tails, and raising themselves on their front legs, nod their head vertically, with a quick movement, and try to look very fierce, but in reality they are not at all so; if one just stamps the ground, down go their tails, and off they shuffle as quickly as they can. I have several times observed small fly-eating Lizards, when watching anything, nod their heads in precisely the same manner; but I do not at all know for what purpose. If the Amblyrhynchus is held, and plagued with a stick, it will bite it very severely; but I caught many by the tail, and they never tried to bite me. If two are placed on the ground, and held together, they will fight and bite each other till blood is drawn. Those individuals (and they are the greater number) which inhabit the lower country, can scarcely taste a drop of water throughout the year; but they consume much of the succulent cactus, the branches of which are occasionally broken off by the wind. I have sometimes thrown a piece to two or three when together; and it was amusing enough to see each trying to seize and carry it away in its mouth, like so many hungry Dogs with a bone. They eat very deliberately, but do not chew their food. The little birds are aware how harmless these creatures are: I have seen one of the thick-billed Finches (peculiar to the Gallapagos) picking at one end of a piece of cactus—which is in request among all the animals of the lower region—whilst a Lizard was eating at the other; and afterwards the little bird, with the utmost indifference, hopped on the back of the reptile. The stomachs of several that I opened were full of vegetable fibres and leaves of different trees, especially of a species of Acacia. In the upper region they live chiefly on the acid and astringent berries of the guayavita, under which trees I have seen these Lizards and the huge Tortoises feeding together. To obtain the acacia leaves, they crawl up the low, stunted trees; and it is not uncommon to see one, or a pair, quietly browsing, whilst seated on a branch several feet from the ground.

"The meat of these animals, when cooked, is white; and by those whose stomachs rise above all prejudices, it is relished as very good food. Humboldt has remarked, that in intertropical South America, all Lizards which inhabit dry regions are esteemed as delicacies for the table. The inhabitants of the Gallapagos say, that those inhabiting the damp region drink water, but that the others do not travel up for it from the sterile country, like the gigantic Land Tortoises. At the time of our visit, the females had within their bodies numerous large elongated eggs. These they lay in their burrows, and the inhabitants seek them for food."

These two curious Lizards of the Gallapagos agree nearly in general structure, and in many of their habits; and neither of them has that rapidity of movement which is characteristic of various other IguanidÆ. The form of the head resembles a good deal that of a land Tortoise, and we find the same form of head, and again the same disinclination to bite, in certain herbivorous Lizards, such as the Uromastyx and kindred forms, which are referred by Dr. Gray to the corresponding Old World family of AgamidÆ.]

In the family of Iguanas the Basilisk may be noted. According to ancient authors, reproduced by writers of the middle ages, the Basilisk, although such a small animal, could produce instant death by its sting. The man whose eyes met theirs was supposed to be at once devoured by an intense fire. Such are the fabulous ideas which tradition has transmitted to us about these animals. It is to be remarked, however, that the Basilisk of modern herpetology is not the as???s???, or Royal Serpent, of the ancients, the Cockatrice of Scripture. The reptile which now bears the name is an inoffensive animal, living in the forests of Guiana, Martinique, and Mexico, and leaping from branch to branch, in order to gather the seeds or seize the insects on which it feeds.

The Basilisk is distinguished from the other Iguanian Lizards by the absence of the long and dilatable skin under the throat, and by the presence of an elevated crest which runs along the whole length of the back and tail.

Fig. 29.—Hooded Basilisk.

The Hooded Basilisk, B. americanus (Fig. 29), measures seven or eight inches from the nose to origin of the tail, which is itself nearly three times as long, being nineteen or twenty inches in length. Upon the occiput it has a sort of horn or bag, in shape like a hood, round at the summit, and slightly inclined towards the neck. This bag, when distended, is about the size of a pullet's egg. In the male the back and tail are surmounted by a raised crest, such as we have described above, sustained in its thickness by the knotty process of the vertebrÆ. The general colour is a mixture of sandy brown, slightly marbled on the back and sides, with shades of blue on the upper part, and a silvery white underneath. On the throat are larger bands of brown, and on each side of the eye is a white ray bordered with black, which is lost upon the back; and the tail is so remarkably attenuated towards its extremity as to show the articulations of the vertebrÆ beneath.

[According to Mr. O. Salvin, the Basilisk is very common about Lanquin, in the province of Guatemala, where it may frequently be seen on the low branches of a bush, and it is particularly fond of basking on the boughs of a felled tree in a clearing near a stream. In some specimens of the males, we are informed, the tail is much more compressed than in others. In a series of the young the crest is shown in all stages of development. We also learn from this naturalist that, notwithstanding the compressed form of its tail, the Basilisk does not habitually enter the water, as most writers have supposed.

The sub-family of Anoles (AnoliinÆ) have mostly the skin of their toes widened (under the ante-penultimate phalanx) into an oval disk, striated crosswise underneath, which enables them to attach themselves to various surfaces. They do not attain the large size of the Iguanas, and the habits and characteristics of the various species inhabiting Jamaica are thus vividly described by Mr. P. H. Gosse in his "Naturalist's Sojourn" in that beautiful island. "The stranger," he remarks, "walks into the dwelling-house. Lizards, still Lizards, meet his eyes. The little Anoles (A. iodurus, A. opalinus, &c.) are chasing each other in and out between the jalousies, now stopping to protrude from the throat a broad disk of brilliant colour, crimson or orange, like the petal of a flower, then withdrawing it, and again displaying it in coquettish sport. Then one leaps a yard or two through the air and alights on the back of his playfellow; and both struggle and twist about in unimaginable contortions. Another is running up and down on the plastered wall, catching the Ants as they roam in black lines over its whitened surface; and another leaps from the top of some piece of furniture upon the back of the visitor's chair, and scampers nimbly along the collar of his coat. It jumps on the table;—can it be the same? An instant ago it was of the most beautiful golden green, except the base of the tail, which was of a soft, light, purple hue; now, as if changed by an enchanter's wand, it is of a dull sooty brown all over, and becomes momentarily darker and darker, or mottled with dark and pale patches of a most unpleasing aspect. Presently, however, the mental emotion, whatever it was—anger, or fear, or dislike—has passed away, and the lovely green hue sparkles in the glancing sunlight as before."

The green colour of certain of these Anoles so closely resembles that of foliage, that they are apt to be overlooked. Thus Mr. Gosse was about to throw a net over a Butterfly, when, as he remarks, "on a slight rustle among the leaves, I observed that it was fluttering as if unable to get away. My impression was that an invisible Spider's-web was holding it; but, looking closer, I found that a little green Anolis had the Butterfly in its mouth. Its colour was so exactly that of the verdant leaves of the bush, that I had not perceived it before, although my eyes were fixed on the spot. I have also observed the same species feeding on Ants. On a gateway a number of scattered Ants of a small kind were running to and fro, as they very frequently are seen to do. A beautiful male Anolis had stationed himself on the post perpendicularly, with the head downwards, and as the Ants one by one came near him he snapped them up. Each capture was the work of an instant; he touched the post with his muzzle, and the Ant was gone: they were evidently seized with the lips, not with the tongue. These little creatures are as playful as they are pretty. As they creep about they often catch sight of another of the same species; immediately one suddenly raises and depresses the head and fore-parts, flirts the tail from side to side, and extends the goitre by means of the elastic arched bone in front, till its tip reaches nearly as far as the muzzle. The brilliant goitre is thus alternately extended and relaxed several times. After being thus 'signalized' for a few seconds, one darts towards the other, who usually runs away, apparently as if wishing to be caught." Elsewhere Mr. Gosse describes the noosing of an example of a fine Lizard of this Anolis group, the DactylÆ Edwardsii, which is also a native of Jamaica, "about a foot long, and of a lively green colour. He was very savage, biting at everything near: presently his colour began to change from green to blackish, till it was of an uniform bluish black, with darker bands on the body, and a brownish black on the tail; the only trace of green was just around the eyes." He was placed in a cage, and "at night," continues Mr. Gosse, "I observed him vividly green as at first—a token, as I presumed, that he had in some measure recovered his equanimity. The next day he continued very fierce. I hung the cage out in the sun; two or three times in the course of the day I observed him green, but for the most part he was black. The changes were rather quickly accomplished. The food of this Lizard appears to include both vegetable and animal substances. I was never able to induce one to eat in captivity; but the dissection of several has given me this result. Thus in one I have found seeds and farinaceous substance; in another the fragments of a brilliant beetle of the weevil group. I once observed one deliberately eat the ripe glass-berries, munching half of one at a mouthful."23

Thus far we have treated of chiefly arboreal IguanidÆ; and although a Marine Lizard (Trachycephalus cristatus) cannot well be so designated, it nevertheless belongs to the same particular series. We have next a long series of mainly terrene genera of the same great American family, in which the body is subtrigonal or depressed. As many as twenty-two genera, with sixty-one species of the terrene IguanidÆ, were catalogued by Dr. Gray in 1845, and a good many have since been added. There is a corresponding series in the kindred Old World family of AgancidÆ, and in neither instance are the majority of them ground-frequenting Lizards to any great extent. Thus, of Dr. Gray's first genus Tropidolipis (so named from its large keeled scales), and of which as many as nine species are given from Mexico, a tenth (T. undulatus, of the United States) is described by Professor Holbrook to inhabit chiefly the pine-forests, where it is often found under the bark of decaying trees; it also commonly chooses old fences for its basking-place. "It is exceedingly rapid in its motions, climbing with great facility to the tops of trees, and is hence not taken alive without great trouble. Its food consists of insects, especially such as are found under decaying wood." The colouring of this Lizard is remarkably brown, with narrow zigzag black bands above, and green below, with a white medium stripe bordered with black; throat and breast black, with a broad green band across. Various species of kindred genera were collected by Mr. Darwin, and are figured in the "Zoology of H.M.S. Beagle," and of one of these (probably LecolÆnus Darwinii), which he observed at Bahia Blanca, in Northern Patagonia, he remarks that "it lives on the bare sand near the sea-coast, and from its mottled colour, the brownish scales being speckled with white, yellowish red, and dirty blue, can hardly be distinguished from the surrounding surface. When frightened it attempts to avoid discovery by feigning death, with outstretched legs, depressed body, and closed eyes: if further molested, it buries itself with great quickness in the loose sand. This Lizard, from its flattened body and short legs, cannot run quickly." With others these Lizards constitute the sub-family TropidolepinÆ of Dr. Gray, which are followed by the sub-family PhrynosominÆ, in which some very singular Lizards find their place. The most extraordinary of them constitute the genus Phrynosoma, four species of which inhabit Western North America. These have great spines to the occiput, in these respects resembling the African genus Cordylus (p. 107), and very Toad-like proportions, looking somewhat like Toads with short tails; and again they decidedly approximate in appearance to the curious Moloch horridus of Western Australia, which belongs to the corresponding Old World family of AgancidÆ; and, like that strange reptile, they are slow of motion, and perfectly harmless, and they may be handled with impunity, as they never attempt to bite.]

Flying Lizards.

Flying Lizards (Draco) have the head small, the nostrils in a scale, tubular, on the side ridge; tympanum white and opaque. They live on trees, walking with agility with their wings folded by their sides. These wings they expand and use as a parachute when they throw themselves upon their prey from the tops of trees or other elevated places. But they cannot move them as birds do their wings. These remarkable appendages also serve to drive away insects.

[The fabulous Dragons of the ancient Greeks were Serpents or Lizards with remarkably piercing sight, which guarded treasures and devoured men. The Dragons of mediÆval artists were frightful and fantastic beings, one half Bat and the other half quadruped or Serpent. The little Saurians which now bear the once dreaded name are no less interesting, although they are no longer monsters; they are distinguished from all other reptiles by a kind of wing, which is a large fold of skin, or membrane, on each side of the body. These wings are entirely independent of the other members, being sustained by six false ribs, which do not surround the abdomen, but rather extend horizontally. They are the only existing examples of our day of that organic arrangement which distinguished the reptiles known under the name of Pterodactyli, and which belonged to the jurassique period of geology.

Dr. Gray divides the Draconina into three genera, namely:—

I. Dracos, having the ears naked, nostrils below the fore ridge, of which three species are described—viz., D. volans, the Flying Lizard (Fig. 30), having the scales of the back broad, generally smooth, those of the throat granular; wings grey, fulvous, or brown, spotted and marbled with black, sometimes forming four or five oblique black bands near the outer edge; the sides with a series of large keeled scales: the Timor Flying Lizard, D. viridis Timorensis of Schlegel; and the Fringed Flying Lizard, D. fimbriatus, keeled.

II. Draconella, of which there are two species, one D. Dussumieri, having the nape crested; and D. hÆmatopogon, the Red-throated Dragon, without crest on the nape.

III. Dracunculus, of which five species are described—namely, D. quinquefasciatus, the Banded Flying Lizard, nape not crested, having a longitudinal fold; D. lineatus, having the nape crested, the ears slightly concave; D. ornatus, wings grey, reticulated with black, and having broad black bands at the edge; the Spotted Winged Dragon, D. maculatus, grey, and the wings black spotted; and D. spilopterus, having the wing reddish near the body.]

GeckotidÆ, or Thick-Tongued Lizards.

This singular family of Saurians have the head wide and flattened, the mouth wide, the nostrils distant and lateral, the eyes large, with short lids; the tongue short, fleshy, and capable of slight elongation. The body is thick and short, low on the legs, rather squat and depressed, with a belly trailing on the ground; back without crest. The skin is defended by granular scales, interlaced with others of a tubercular character; they are almost always of a sombre colour. Their feet are short, wide apart, and robust; they are furnished on the upper part with imbricated laminÆ, which enable them to adhere firmly to the surface of even the smoothest bodies, and to run with rapidity in all directions on a plain surface, and even to remain stationary with the back downwards, like the common house Fly. More generally, however, their hooked and retractile claws, like those of cats, assist them in climbing, crawling up trees, rocks, and even perpendicular walls, and to remain there immovable for several hours. Their flexible bodies mould themselves into the depressions of the surface of the earth, in which they become scarcely visible, their natural colour blending, and being confounded with, the colour of the soil. Their eye-balls, which dilate and contract considerably, protect them from the action of the sun's rays, and enable them, it is thought, to see in the dark. They are nocturnal, avoid the sun's rays, and catch their food in the chinks of rocks. Their movements are rapid, silent, and sudden. They hibernate, and are provided with fatty masses in the groin which are supposed to be a provision for their nourishment during that period. Geckos emit sounds which resemble the noise an equestrian makes when he would encourage his horse—smacking their tongues on the palate to produce the sound. They seek habitations in which they can find food, and are timid, inoffensive, and quite incapable of inflicting injury either by their bite or claws; but their repulsive appearance makes them objects of general repugnance, and has caused evil properties to be attributed to them. Thus people try to destroy them by every possible means. There are about sixteen known species of Geckos distributed in all quarters of the globe, but chiefly in warm countries.

[The GeckotidÆ are divided into many genera, according to the construction of the toes. DumÉril refers to the comparative shortness and general structure of the feet and conformation of the toes, which he describes and figures in detail. The lower surface and the sole he states are very dilatable, and furnished with small plates or lamellÆ, following or overlying each other in a mode which varies in the different species. The nails are sometimes wanting on all the toes, but more frequently hooked, and more or less retractile; the toes sometimes united at the base, and in Platydactylus the extremity of the toe expands into a fan shape, as in the Tree Frogs. The membranous and soft plates of the lower surface of the toes have various modifications in different genera, which have been made the basis of their arrangement. The Wall Gecko is supposed by Gesner to be the Lizard spoken of by Aristophanes and Theophrastus, and the Tarentula of the Italians: and there is little doubt that it was the ?a?a?a??e of Aristotle and the ancient Greeks; it clambered about their walls catching spiders, on which it fed. Schneider has shown it was the Stellio of Pliny. LinnÆus mentions three species, which he places with his great genus Lacerta. Modern herpetologists, following Cuvier and DumÉril, class them according to the structure under the several genera Ascalabotes, Platydactylus, Hemidactylus, Ptyodactylus, Thecadactylus, Stenodactylus, and Gymnodactylus.]

The Wall Gecko (P. homalocephalus), Fig. 31, is of an ashy grey colour, as if powdered on the upper part of the body. It is white underneath, and inhabits the islands of the Mediterranean, as well as the countries which form the basin of that sea, such as Italy, France, Spain, and Africa. They are generally found in old walls; they are, however, sometimes seen running on those of modern habitations. They feed on all sorts of insects, particularly on the dipterous insects and Arachnidans.

Chameleo. (Laurenti.)

The genus Chameleo, of which ten species are described in the British Museum Catalogue, are natives of Africa and Asia and naturalised in Southern Europe. They live on trees, clinging to the branches by their feet and prehensile tails; they move slowly and with great caution, feeding upon insects, which they catch with singular dexterity by the rapid elongation of their tongue, which is viscid at the tip.

Certain groundless metaphors, deeply rooted in the popular mind, have singularly distorted the truth in respect to these reptiles. It is commonly believed that the Chameleon often changes its shape, that it has no fixed colour belonging to itself, but takes that of all objects which it approaches. This singular idea has descended from very ancient times. According to the reports of Theophrastus and Plutarch, the Chameleon takes all colours in turn but white; according to Aristotle it changes colour all over the body; but Ælian seems to have had views more in accordance with those of modern observers, for he says when it takes other colours than grey and disguises itself, it covers only certain parts of the body with them. Altogether the ancients made the Chameleon a very fantastic animal; hence in the familiar comparisons of literature these fabulous beings serve as a type to designate uncertain principles; to paint fawning men, who have neither character nor individuality of their own, but who bend themselves to the will and adopt the opinions of others. Putting aside the imaginary attributes accorded to the Chameleon by the fancies of the ancients, and painting them such as they are, we still see in them animals most worthy of observation and highly interesting to the naturalist, as well for the singular formation of different parts of their bodies as for their remarkable habits, and even for peculiarities which have given some sanction to the errors and prejudices to which we have alluded.

Chameleons have compressed bodies; the back round and projecting, or rather pyramidal; the skin granulated; the head angular, with salient occiput resting on a short and thick neck; their legs are slender; the hind, as well as the fore toes are five; the tail prehensile and round. The eyes are very large and protruding, their globes covered by a single shagreen-like eyelid, which the animal can dilate or contract at will, but which leaves little liberty to a small hole pierced at the centre, through which a quick and rather brilliant eye-ball is perceived. The eyes, in the Chameleon, are thus completely enveloped, as if they were too delicate to sustain any glaring light; but this is not all—their eyes have a singular mobility. By certain special muscular arrangements they have the power to direct them on objects either together or separate. Sometimes they turn their eyes in such a manner that one eye looks back and the other forward. With one eye they can see objects above them, while with the other they can see those situated below. It is a common saying in France, applied to the Chameleon, "that it could look into Champagne and see Picardy in flames."

The vermiform and retractile tongue is also a most singular organ. It is cylindrical, about six inches long, terminating in a fleshy, dilatable, and somewhat tubular tip, which is covered with a glutinous secretion, by the aid of which it seizes its insect food, and draws it towards its mouth. The feet have five very long and almost equal strong and hooked claws, but the skin of the legs extends to the end of these toes, and unites them in a very peculiar manner. Not only is this skin attached to each of the toes, but it envelops them, and forms, as it were, two bundles,—the one of three fingers, and the other of two. From this structure one can anticipate the extreme difference which exists between the habits of Chameleons and those of Lizards. These two bundles of long toes are placed in such a manner as to enable them to seize the branches easily on which they love to perch; they can grasp these branches by holding on with one bundle of fingers before, and the other behind, in the same manner as Woodpeckers, Cuckoos, and Parrots. Chameleons are better able to preserve their equilibrium upon trees than upon the ground; consequently they are more often seen in those Ærial domiciles. Besides, their long and strong prehensile tail serves them as a fifth limb. They swing themselves about like monkeys, grasping the small branches, and thus saving themselves from falling. Moreover, they are cautious, moving at all times very slowly when going from one branch to another. Walking becomes much more difficult for them when they rest upon a level surface—groping their way as they advance, placing their feet upon the earth, one after the other, with the greatest circumspection. They also steady themselves on the ground by the aid of their tail. In their walk they display a certain gravity which contrasts with their diminutive size and the agility which might be expected from them. Even when perched upon a tree their movements exhibit a slowness and deliberation that one would be inclined to say was affected. It is true that the arrangement of their eyes, and the rapid movements of their tongue, render personal activity superfluous in their search for food. They can see their prey and their enemies from a great distance, and in all directions. The latter they readily avoid. As to their prey, when about to seize it, the Chameleon rolls round its extraordinary eye-balls so as to bring them to bear on the devoted object. As soon as it arrives within range of the tongue, that organ is projected with unerring precision, returning into the mouth with the prey adhering to the viscous tip. This tongue they can extend to a length sometimes surpassing that of their body. The skin of the Chameleon does not adhere to the muscles everywhere; some spaces are left free, into which the air penetrates, causing the skin to heave and swell; this mechanism is voluntary, the animal having the power of inflating or relaxing it at pleasure. When this great living bladder is emptied, the animal may be said to resemble a bag of gold-beaters' skin filled with bones. Chameleons exhibit great variation in their colours; that is to say, they may be almost white, sometimes yellowish, at other times green, reddish, and even black, either in portions, or all over their bodies. These changes of colour were for a long time attributed to the greater or less distention of the vast lungs they possess, and to the corresponding modifications in the quantity of blood sent to the skin; but this explanation is now abandoned. According to Mr. Milne Edwards, the cause of these variations of colour lie in the peculiar structure of their skin, in which there exists two layers of membranous pigment, placed the one above the other, but disposed in such a manner as to appear simultaneously under the cuticle, and at other times so that the one hides the other. Again, occasionally the cuticle is hidden under the superficial pigment.

[Sixteen or seventeen species of Chameleon are described in the British Museum Catalogue.

I. Having an erect fin on the back, the belly crested; which includes the Fringed Chameleon, C. cristatus, a native of Fernando Po.

II. Having the back high, and compressed belly and sides, with a toothed crest; including the Side-crested Chameleon, C. laterales, a native of Madagascar.

III. The back and belly having a toothed crest, the sides simple, the scales small and equal, muzzle simple; including the Common Chameleon, C. vulgaris, with many synonyms. It is a native of the East Indies, is the recognised type of the family (Fig. 32), and the one most commonly brought to England. There are probably two varieties,—one from North Africa, which is also found in Sicily and the South of Spain; the other, the East Indian variety—C. Senegalensis, the Senegal Chameleon, a native of West Africa; C. arpelis, from Ashantee and Gaboon; C. verrucosus, a native of Bourbon and Madagascar; the Rhinoceros Chameleon, C. rhinoceroceratus, also from Madagascar.

IV. Having a toothed crest on the back, with the belly and sides simple, the chin and muzzle simple; including C. tuberculiferus, a native of South Africa; C. cucullatus, the Hooded Chameleon, a native of Madagascar; C. nasutus, having the chin simple, and the muzzle compressed, and C. bifurcus, having the muzzle in the male forked—both natives of Madagascar; C. Tigris, Seychille Islands; C. ventralis, from South Africa, and C. pumilus, from the Cape of Good Hope.

V. Having back and belly without crest; including C. Parsonii, a native of Madagascar; and C. Owenii, the Three-horned Chameleon, from Fernando Po, and C. Brookesianus, an adult species, from S. W. Brookes's collection.

Emydosaurians

Have the head large, covered with a thick skin, ears closed with two valves, gape very wide, tongue short, jaws with a single series of cone-shaped teeth inserted in sockets; back with a hard disc formed of a longitudinal series of square keeled plates of hard bony consistence embedded in the skin; the under surface covered with smooth thin square plates; legs short, feet webbed, with four to five toes, the three inner toes of each foot only armed with claws.

They are divided into two groups:—

I. CrocodilidÆ, having the lower canines fitting into a notch in the edge of the upper jaw.

II. AlligatoridÆ, having the canines fitting into a pit in the upper jaw.]

Crocodiles.

The Shielded Saurians, as DumÉril designates the largest of living species of that order of reptiles, have the body depressed, elongated, and protected on the back with a solid carinated shield or buckler; the tail longer than the trunk, compressed laterally, annulated and crested above; having four very short feet; the toes of the posterior feet united, or web-footed, each foot having three claws only; head depressed and elongated into a muzzle; the gape of the mouth extending back beyond the skull; tongue fleshy, adherent; teeth conical, simple, hollowed at the base or towards the root, unequal in length, and in a single row. Such is a brief summary of the family by DumÉril and Bibron.

If the Eagle is the king of the air, the Tiger and the Lion the tyrants of the forests, and the Whale the monarch of the deep, the Crocodile has for the exercise of his undisputed control the maritime shores of tropical seas and the borders of tropical rivers. Living on the confines of land and water, this formidable reptile is at all times the scourge of those human beings who are compelled to reside near its haunts. Much larger than the Tiger, Lion, or Eagle, the Crocodile surpasses all terrestrial animals, with the exception of the Elephant, Hippopotamus, and some Serpents, in its power of destruction.

Crocodiles have the head depressed and elongated into a muzzle, in the front of which the nostrils are seen close to a fleshy tubercule, and furnished with movable valves. The mouth opens up to the ears; the jaws are of commensurate length, and are armed, as we have seen, with conical-pointed teeth, bent back, and disposed in such a manner that when the mouth is closed they pass one under the other. These teeth are implanted in a single row, and continually maintained in a good condition by an organic system which ensures their immediate reparation. In short, each tooth is hollowed at the base in such a manner as to form the cell or sheath of another tooth of a larger calibre. The new tooth, which presses on, exercises a sort of absorption upon the base of the old hollow tooth, so that the first is developed while the second is decaying. In some species the front teeth of the lower jaw are so long and sharp that they perforate the edge of the upper jaw and appear above the muzzle when the mouth is closed. The lower jaw alone is movable, and that only in a downward movement. The mouth is without lips, consequently, whether walking or swimming, the teeth of Crocodiles are always visible.

This formidable conformation gives to the Crocodile an aspect at once terrible and alarming, which is increased by two wicked-looking eyes placed obliquely and close together, surmounted by a kind of eyebrow. The tail of these animals is very long, as thick as the body at the junction, and in shape it is flat, like an oar; this enables them to steer through the water like a fish, and to swim with rapidity. They have four short legs, of which the hinder have toes, united by a natatory membrane, and only three claws to each foot. The skin is coriaceous, thick, and resistant; being also protected by very thick knots intermingled with plates of different size, according to the parts of the body they protect. On the skull and face the skin adheres closely to the bone, and there is no trace of scales.

Nature has provided for the safety of these animals by covering them with a cuirass, the resistance of which is proof against almost everything. Thus the scales which defend the back and the upper part of the tail are square, and form hard transversal bands possessed of great flexibility, which prevents them from breaking. Down the centre of the back there is a hard crest, which adds to the strength of their armour. This cuirass is in many points proof against a bullet from a gun. The plates which cover the belly, the upper part of the head, neck, tail, and legs are also arranged in transversal bands, but less hard, and without crests. It is at these weaker and consequently vulnerable parts that those inhabitants of the waters which are enemies to Crocodiles manage to attack them successfully.

The general colour of the Crocodile is a dullish brown, with sometimes a shade of green along the back; the head and the sides are marked with green, or at least they have a greenish tint, with blackish spots; the under part of the legs and belly are of a yellowish grey. All these shades, however, vary with age and sex, and the nature of the water in which the animals live.

Crocodiles are oviparous, and their eggs are provided with resistant shells. These eggs are deposited by the female in some secluded place in the sand on the banks of the river, and are hatched simply by the ambient heat, without any assistance from the mother. The female Crocodiles of the Nile deposit their eggs where the solar heat soon brings them to maturity. In certain countries, such as the neighbourhood of Cayenne and Surinam, the eggs are buried under a kind of mound which the Alligators raise in damp places by gathering together leaves and herbaceous stems. This vegetable debris undergoes a kind of fermentation, the result of which is an increase of temperature, which, joined to that of the atmosphere, produces the desired result.

LacÉpÈde describes an egg in the Museum of Natural History in Paris, which was laid by a Crocodile fourteen feet in length, which was killed in Upper Egypt. This egg is only two inches and five lines in its greatest diameter; in its least diameter it is one inch and eleven lines. It is oval and whitish. Its shell is cretaceous in substance, like the eggs of birds, but not so hard. At the time of their birth the little Crocodiles are only about six inches in length, but their growth is very rapid. They abound in large rivers in the tropics, and in marshy places near their banks. They often come on shore, for they are amphibious. In the night they watch for their prey. They feed exclusively on flesh—that is to say on fish, small Mammalians, aquatic birds, and reptiles. When they have seized a large object they drag it under the water, where it soon dies by asphyxia; there they leave it to macerate, when they eat it by instalments. In this manner men are sometimes carried away by Crocodiles, but it is contrary to the habits of the animal to suppose that they are devoured immediately. When a Crocodile has succeeded in seizing a negro, it does not devour him till the body becomes decomposed, when it can tear it to pieces with greater facility.

From the general structure of their bony framework it is difficult for Crocodiles to turn round or move otherwise than forward. This circumstance renders it easy to escape their pursuit. When chased by a Crocodile, it can be avoided by describing a circle, or running in a succession of curves. Upon the banks of the Lake of Nicaragua, in America, an Englishman was once pursued by an Alligator which had surprised him when on its margin. The animal was gaining upon him rapidly, when some Spaniards who witnessed the scene cried out to him to run round it. Thus fortunately warned the pursued dodged the Alligator, and escaped from his dangerous enemy (Fig. 33).

[No specimens of the CrocodilidÆ have been found in Europe, and until very recently none had been found in Australia, but they are very common in the new colony of Queensland, an Alligator twenty feet long having been shot on the banks of the Mackenzie river, which was afterwards exhibited at Rockhampton. Crocodiles, properly so called, are found in Africa, Asia, and America. The Gavials seem to be limited to the Ganges and other large rivers in India. Besides the Gavial, Asia produces three other species, namely, C. vulgaris, C. galeatus, and C. bifurcatus. Of the first, Siam is the chief locality; the others are found in the rivers which debouch into the Indian Ocean and the Ganges.

The AlligatoridÆ

Include the Jacares, Alligators, and Caimans.

The Jacares have the head oblong and depressed, with a ridge across the face in front of the eyes; teeth unequal, canines of the lower jaw fitting into a pit in the upper jaw; toes only partially webbed, eyelids fleshy, nostrils separated by a cartilage. Five species are described—namely, J. fissipes, from Tropical America, six feet in length; J. sclerops, from the Brazils; J. Nigra, also from the Brazils; J. punctulatus, with triangular oblong head, muzzle elongated, thin and flat, with a rounded point in front, and a slight enlargement behind the nostrils; J. vallefrons, differing slightly from the above—both natives of the Brazils.

Alligators have the jaws oblong, much depressed, broad and nearly parallel; forehead with a small longitudinal ridge between the orbits; feet fringed, toes half webbed, the outer toes free; nostrils separated by a bony septum rising from the upper edge, muzzle lengthening with age. One species only is known, which is a native of North America; it attains a length of six to seven feet, and is known also as Crocodilus Mississipensis.

The Caimans have the jaws oblong, depressed, rounded, and swollen at the end, without frontal ridges or maxillary pits; teeth unequal, the lower canines fitting into pits in the upper jaw; toes webbed. There are three species described—C. trigonatus, C. palpebrosus, and C. goddeceps, all natives of Tropical America.

The Jacares, Alligators, and Caimans are natives of America, which country is fruitful in other species of the family. C. acutus is also found in Martinique and San Domingo; C. rhombifor, at Cuba; A. palpebrosus, A. sclerops, A. punctulatus, and A. cynocephalus are natives of the southern part of the American Continent; and A. lucius is found in the north.]

The principal characteristics of the American Crocodile are a head one-third its length, and a very short muzzle; teeth unequal in shape and size, the fourth lower tooth being buried in the upper jaw when the mouth is closed; the first teeth of the lower jaw piercing the upper at a certain age, so as to appear through the muzzle when closed. The hinder legs and feet rounded, having neither crest nor indentation on their edges; the intervals of the toes more than half covered with a short membrane, forming semi-palmated feet.

It is generally admitted, as we have stated above, that there are five species of this genera, all exclusively American, the type of which is the Alligator, or Caiman. A. Mississipensis (Gray) belongs properly to North America, through the whole southern extent of which it is found. They are gregarious, living together in large herds in the Mississippi and its southern tributaries; they are also found in the lakes and marshes of Louisiana, Carolina, and even as far north as thirty degrees of north latitude. Alligators do not appear to leave fresh water. During the winter season they bury themselves in the mud of the marshes, and await in a state of torpor the return of spring, which is the signal of their restoration to activity. In the neighbourhood of Bayou Sarah, on the Mississippi, flats of lakes and marshes stretch away to a vast extent on either bank; every year these reservoirs are flooded by the overflow of the river, when they are visited by myriads of fishes. The heat soon partly dries up these lakes, leaving only about two feet deep of water, thus displaying a vast amount of prey ready prepared for the shore birds and Crocodiles. Millions of ibis, herons, cranes, and cormorants wade into the water in pursuit of these fish. In the deepest portions vast quantities of these imprisoned fish accumulate, and these parts are known in the country as the Alligators' holes. Thither these reptiles crowd, pressing one against the other, and they soon thoroughly clear it of the fish which lately were in such dense crowds. As evaporation proceeds and the marshes gradually dry up, the fish are more and more exposed to their voracious enemies. The Alligators pursue and devour them in the water, whilst the ibis destroys those which seek the banks for refuge. Alligators fish chiefly during the night. In the hours of darkness and obscurity they assemble in large herds, chase the fish before them, driving them into some retired creek, where they rejoice their hearts at the expense of the unfortunate finny tribes, which they force into their widely opened mouths by a lateral movement of their tails. On these occasions the clashing of their jaws may be heard at the distance of a mile. Alligators are found by thousands in Mexican waters, and nearly all North American rivers to the south of them. In the beautiful transparent waters of Lake Claro they abound, and are without difficulty seen by the naked human eye. Here they are so closely pressed one against the other that they resemble a raft of trees recently felled, and the resemblance is further increased by the colour of their backs and the bark of a newly-felled tree being identical. In this united and immovable condition, while waiting for their prey, the approach of a boat is disregarded; but they rush with avidity at everything animate which either falls or is thrown into the lake. Many children of poor negro women become a prey to the Caiman in this locality. They rarely, however, pursue men, yet they would not hesitate to devour them if their imprudence has placed them close to their terrible jaws.

The natives of Mexico hunt the Caiman. When they meet an isolated individual asleep, they throw a lasso round its body, and when secured, gag it. After this operation, the victim's career is terminated by hammering on his head. There is another means which the Indians use to capture the Caiman. They provide themselves with four pieces of hard wood about a foot long, and as thick as a man's finger, and pointed at each end; round these they tie a cord in such a manner that, supposing the cord to be an arrow, the four sticks would form the head of it. They then fasten the other end of the cord round a tree, and bait with meat. This device is thrown into the water. When the Caiman snaps at the prey the points of the hook, on straining on the line, penetrate into its flesh. Having waited till the Alligator is dead, it is drawn from the water, when the captors further gratify their dislike and spirit of revenge by breaking its skull with stones and sticks.

Another method of capturing Alligators is practised by the residents on the upper waters of the giant river Orinoco. A tree is bent (generally a bamboo is selected from its elasticity) till the top is brought down to the butt, a bait is then placed on a sharp hook, the line attached to it being fastened securely to the small end of the bent tree, which is caused to relax its position by an ingenious piece of mechanism which gives way the moment the least strain is felt upon the line; the tree-point becoming thus released, straightens itself with great velocity, and drags the victim from the water.

Frequently the Alligator, from constant pursuit and interruption, becomes excessively wary and difficult to destroy; when such is the case, a live bait is sometimes successfully employed. For instance, a Dog with a hook tied to his back is taken in a canoe and dropped in the water; it is seldom the unfortunate cur is permitted to swim far before being seized.

It is currently believed that the Alligator prefers dog-flesh to all others. The negroes on the plantations in the South-Western States of America, by imitating the barking of a dog, frequently lure these reptiles from their hiding-places, when a well-directed bullet terminates their career.

Alligators are very voracious, but, like Serpents and Turtles, they can live a long time without nourishment. In Brown's "Natural History of Jamaica," he asserts that he has known the Caiman to live several months without food. The following experiments have been tried in that island:—The mouth of an Alligator was muzzled by a strong cord, it was then thrown into a reservoir of water. Thus these animals lived a considerable time. They were seen to rise occasionally to the surface of the water, until death came to their rescue. Let us add to this, that Crocodiles bred in captivity in the menagerie of the Museum of Natural History, at Paris, sometimes live for several months without eating.

The female Alligator takes more care of her young than the female Crocodile, properly so called. She conducts them to the water, and in the slimy mud she disgorges her half-digested food for their nourishment.

The true Crocodiles are indigenous to Africa, but they are found also in Manilla and India. Their length of head is almost double its breadth. The fourth tooth of the lower jaw is the longest and largest of all, and passes into an indentation hollowed out in the edge of the upper jaw, becoming visible on the outside. The hind feet have on their external edge a dentated crest, and the interstices of their toes, externally, are palmated.

The principal type is the Common Crocodile, C. vulgaris, which sometimes attains the length of nine or ten feet. The upper part of the body of these reptiles is of an olive green colour spotted with black, and marbled upon the head and neck with the same colour, also the back and tail; two or three broad, oblique black bands are visible upon the flanks of the under part of the body, which is of a yellowish green. Crocodiles abound in Africa. Formerly they were found in all parts of the Nile, but lately it is said that C. vulgaris is no longer to be met with in the Delta, but that it exists in great numbers in the Thebaid and in the Upper Nile. They are also found in the rivers Senegal and Niger, in Caffraria, and in Madagascar. Most authors give them the name of Crocodiles of the Nile. This species are found also in India.

The Crocodile was considered a sacred animal by the ancient Egyptians. In ruins of temples mummies of Crocodiles are still found in a perfect state of preservation. The Romans introduced living Crocodiles at the national games in the Colosseum. At first only five were imported under the Ædileship of Scaurus. Under the Emperor Augustus thirty-six were killed in the Circus of Flaminius. Several ancient medals represent this reptile, the body of which perfectly resembles that which now lives in the waters and on the banks of the Nile. There is a truly wonderful fact in the natural history of the Crocodile. Listen to what Herodotus, the father of history, tells us with regard to it:—"When the Crocodile takes his food in the Nile, the interior of its mouth is always covered with bdella (flies). All birds, with one single exception, flee from the Crocodile; but this one, the Nile Bird, Trochylus, far from avoiding it, flies towards the reptile with the greatest eagerness, and renders it a very essential service. Every time the Crocodile goes on shore to sleep, and at the moment when it lies extended with open jaws, the Nile Bird enters the mouth of the terrible animal and delivers it from the bdella which it finds there; the Crocodile shows its recognition of the service, and never harms the bird."

This fact, reported by Herodotus, was long considered to be a fable, but the naturalist, Etienne Geoffroy Saint-Hilaire, who formed part of the commission that General Bonaparte took with him in his expedition into Egypt, had on several occasions opportunities of proving the truth of the historian's narrative.

In a memoir read to the Academy of Science on the 28th of January, 1828, he says, "It is perfectly true that there exists a little bird which flies about, perpetually seeking, even in the mouth of the Crocodile, the insects which form the principal part of its nourishment." This bird, which Geoffroy Saint-Hilaire recognised as the Charadrius Ægyptius of ornithologists, is like a Plover. The bdella, which thus torment the Crocodiles, and even excite them to madness, are no other than our European gnats. Myriads of these insects haunt the banks of the Nile, and when these giants of its waters repose on its margin, warming themselves in the sun, they become the prey of these insignificant pigmies. It is like the war between the Lion and the Mouse, described by La Fontaine. The bdella fly into the Crocodiles' mouths in such numbers that they cover the entire surface of the palate, and form a brownish crust. These little pests pierce the tongues of the reptiles with their stings. It is then that this bird comes into the mouth of the monster to catch them, and deliver it from such innumerable enemies. The Crocodile with one bite could easily destroy the bird, but he knows too well what he owes to this friend to do it an injury. Crocodiles of the Nile are more voracious than the American Alligators. Hasselquist asserts that in Upper Egypt they often devour women who come to draw water from the Nile, as well as children playing upon its banks. Geoffroy Saint-Hilaire says, that in the Thebaid they often met with Arabs wanting an arm or leg, who accused Crocodiles of this mutilation. Sir Samuel Baker also mentions, in his late work on the Nile and its tributaries, the desire of these amphibia for human flesh, and the dread they are held in by the natives. Livingstone, the celebrated traveller, gives the following account of an encounter he had with one of these ferocious animals:—

"The Crocodile," says the celebrated traveller, "makes many victims every year among the children who are so imprudent as to play on the banks of the Liambia when their mothers go to fetch water. The Crocodile stupefies its victim with a blow from its tail, then drags it into the river, where it is soon drowned. In general, when the Crocodile perceives a Man it dives, and furtively glides away from the side which he occupies. Sometimes, on the other hand, it precipitates itself with surprising agility towards the person it has discovered, which may be noticed from the disturbance caused on the surface of the water. An Antelope which is being hunted and takes to the water, in the lagunes of the BarotsÉ valley, a Man or a Dog who goes there to seek for game, will scarcely fail to be seized by a Crocodile, of whose presence he has not the slightest suspicion. It often happens that, after having danced in the moonlight, the young natives of the river's bank will often plunge into the water in order to refresh themselves, when, being seized by an Alligator, they perish."

[This mode of attack (striking with the tail) is also one of the methods adopted by the Alligator of America for disabling its prey. A friend, on whose veracity I have much dependence, while shooting wild fowl on one of the tributaries of the Lower Mississippi, had the fortune to witness a fight between a Bear and an Alligator. He was called to the scene of the struggle by the noise made by the combatants, in the dry cane, that yielded to their pressure as they fought in each other's embrace. Several times both ceased only to recover breath and fresh energy; at length the Alligator missed striking the foe with its tail, Bruin seized the opportunity, and with all his efforts succeeded in turning the amphibian on its back, where he held him for some minutes, at the same time gnawing one of the fore-shoulders. A final struggle of the now worsted Alligator hurled both into the water, where they disappeared, the disturbed surface telling of the dreadful contest that was being prolonged beneath; after the lapse of over a minute the Bear came up, evidently much fatigued, and swam ashore, my friend forbearing to wound, or possibly kill, the gallant conqueror.]

Crocodiles, it is said, which have never eaten human flesh, are much less dangerous than those that have acquired a taste for it. Mr. Combes states that he was assured by an inhabitant of Khartoum, who had reached the town with the Egyptian troops—that is to say, before the horrors committed by the Desterdar, acting with Mehemet Bey, who had been Governor of the Soudan some time before Mr. Combes's voyage—that the Crocodiles appeared to be quite indifferent to human flesh; but after the many executions by drowning ordered by Mehemet Bey, as he was told by a native whom he interrogated—"since the Nile has been loaded with the carcasses of my brethren"—the monsters which inhabit it have become habituated to substantial food, which they scarcely knew before: so that afterwards those swimming in the river, or even bathing on its banks, were exposed to imminent danger.

Natives of Africa shoot the Crocodile with a gun, or attack it with a barbed javelin, which is thrown by hand, and aimed at the fore-shoulder. Some Egyptians are reported to be daring enough to swim under the Crocodile, and pierce him in the belly with a dagger. The negroes of Senegal are said to be equally expert. If they surprise the animals in parts of the river where there is not sufficient water for them to swim, they attack the monster with a lance; and with their left arm wrapped in a sheet of leather, they commence by aiming with their weapon at the eyes and throat; then they thrust the arm, encased in leather, into its mouth, and, holding it open, their enemy is either suffocated or expires under the wounds received. Traps are also employed successfully for their destruction. In Egypt the natives dig a deep hole in the ordinary route of the Crocodiles, which is easily discovered by the trail they leave in the sand. This hole is covered with branches and strewed with earth. The Crocodile is now alarmed with loud cries, which disturb and drive him back to the river, by the same way that it has left it. As it passes over the treacherous hole it falls in, when it is killed, often with the most brutal cruelty. At other times a thick cord is attached to a large tree, and to the other end of the cord a lamb is bound, held by a protruding hook. The cries of the lamb attract the Crocodile, which, in its attempt to carry off the bait, is taken by the hook.

Still another method for the destruction of these repulsive-looking creatures has been adopted on one or two occasions by our countrymen in India. A dead animal is procured, in its abdomen is placed a loaded shell, to which is attached a wire made fast to an electric battery; when the bait has been seized and carried to the bottom, the shell is exploded, which invariably maims or kills the Crocodile.

The Gavials, or Indian Crocodiles, have long narrow cylindrical muzzles, slightly inflated at the extremity; the teeth are almost the same, both in number and shape, on each jaw, the two first and the fourth of the lower jaw pass into notches or indentations in the upper jaw, and not into holes, as in Crocodiles; the hind legs are dentated and palmated, like those of African Crocodiles. The Gavials are chiefly remarkable for their long head, its type being the Gavial of the Ganges, or Gavial longirostre. It is of a deep watery green colour, having on the upper part numerous irregular brown spots; in the young, the back and limbs are transversely banded with black; the lower part is of a pale whitish yellow; the jaws are marked with brown, the claws are of a clear horn colour. This species is not so carnivorous as the others, and is consequently less dreaded.

The Gavial of the Ganges, G. Gangeticus, is supposed to be the largest of the existing Saurians; its length, as given by DumÉril, is seventeen feet four inches.


                                                                                                                                                                                                                                                                                                           

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