Photo by W. Saville-Kent, F.Z.S.] _Milford-on-Sea. Photo by W. Saville-Kent, F.Z.S.} [Milford-on-Sea.

FRILLED LIZARD AT BAY WITH EXPANDED FRILL FRILLED LIZARD WITH FRILL FOLDED TIP.

L Photo by W. Saville-Kent, F.Z.S.} [Milford-on-Sea. Pkoto by W. Saville-Kent, F.Z.S.} _Milford-on-Sea.

PRILLED LIZARD RUNNING ON ITS HIND LEGS (VIEW FRILLED LIZARD RUNNING ON ITS HIND LEGS (BROAD-

FROM THE REAR). SIDE VIEW).

567

Photo by W. Saville-Kent, F.Z.S.} (Milford-on-Sea. PRILLED LIZARD RUNNING ON ITS HIND LEGS (VIEW FROM THE REAR).

of the World568 The Living Animals

other circumstances it progresses on all-fours, after the manner of the ordinary members of its class. Several other lizards belonging to the family group of the Agamas have been demonstrated by the writer to move in the same manner as the frilled species. LESEUR'S WATER-LIZARD, also a Queensland form, which attains to a length of 3 or 4 feet, is a notable example in this connection. As implied by its name, it is semi-aquatic in its habits. It frequents scrubs in the neighbourhood of river-banks and backwaters, and passes a considerable portion of its time in shallow water with only its nostrils elevated above the surface. It is a most expert swimmer, sculling itself with grace and rapidity, aided only by its long, laterally compressed tail. Examples brought to England and kept alive for some years by the writer were observed, in hot weather more particularly, to sleep at nights in their water-tanks. The several instances of bipedal locomotion among living lizards, as here chronicled, are of especial interest in correlation with the circumstance that certain extinct Dinosaurs habitually progressed on their hind limbs only. They, in fact, have left " footprints on the sands of time" which indubitably prove this assumption. There is, however, no relationship between the two groups, and the resemblance is one of pure analogy, just as both bats and birds fly, although they have no kinship. Among other interesting lizards included in the Agama Family, mention may be made of the singular JEW or BEARDED LIZARD of Australia a flattened, broad-set form, some 14 or 15 inches long, brown in hue, and clothed with rough imbricated scales, but whose chief peculiarity consists of the expansive beard-like development of the cuticle immediately underneath the animal's chin. As in the frilled lizard, this cuticular excrescence is only conspicuous when the creature is excited, at other times being Photo by W. Saville-Kent, F.Z.S.} [Milford-on-Sea. contracted and indistinguishable from an AUSTRALIAN TREE-LIZARD; When retiring to rest, This species also runs on its hind legs. ordinary skin-fold. these lizards, in their adult state, almost invariably climb up and cling to the rough bark of a convenient tree, and when young and more slender will also ascend saplings, on which they sleep, clinging by their inter-locked claws. is the so-called YORK Another member of the Agama Family which invites brief notice DEVIL, or MOUNTAIN-DEVIL, of Western and Central Australia. This lizard is of comparatively small size, rarely exceeding 6 or 7 inches in length. Its feeble form and stature, however, are abundantly compensated for by the complex panoply of spines and prickles by which its head and limbs and body are effectually protected. The natural food of this singular lizard consists exclusively of ants, the small black, evil-smelling species which often proves itself a pest by its invasion of the Australian colonists' houses being its prime favourite. These are picked up one by one by the rapid flash-like protrusion and retraction of the little creature's adhesive tongue, and the number of ants which are thus assimilated by a Moloch lizard at a single meal is somewhat astonishing. A number of examples of this species were kept by the writer hi Australia, and their gastronomic requirements fully satisfied

Lizards 569

every day by taking them into the garden and placing them in communication with a swarming ant-track. By careful observation it was found that no less than from 1,000 to 1,500 ants were devoured by each lizard at a single sitting. The ant-devouring proclivities of these prickly little lizards can no doubt be turned to very useful and effective account in clearing ant-infested domiciles, and were in fact thus utilised by the writer on more than one occasion.

The lizards included in the Agama Family are essentially inhabitants of the Eastern Hemisphere, none occurring in America. In the western continent, however, we find an equally extensive but structurally distinct group which presents many singularly corresponding types. This family comprises the true IGUANAS, many of them of considerable size, and a numerous assemblage of smaller forms. Among those species which present a striking parallel in size and aspect to the peculiarly characteristic Old World Agamas, mention may be made of the little so-called HORNED TOAD, or SPINY LIZARD, of California and other of the North American States. This species might readily be taken by the uninitiated for a near relation of the Australian Moloch Lizard, or Mountain-devil, last described, its flattened diminutive form and bristling spiny armature seemingly justifying such a supposition. The crucial test afforded by the character of the dentition, however, distinctly indicates its true position to be with the Iguanas. In the Agamas the teeth are invariably developed from the apex, or summit, of

the jaw. These teeth, moreover, are varied in character. In the Iguanas,

on the other hand, the teeth are all more or less uniform in character, and are attached to the outer sides of the jaw.

The larger iguanas are, for the most part, exclusively fruit- and vegetable-feeders, and arboreal in their habits. The thick forest scrubs in the vicinity of streams and rivers are their favourite resort. After the manner of the Australian water-lizards, these iguanas are expert swimmers, and delight in lying along the overhanging branches, whence at the slightest alarm they can precipitate themselves into the water beneath.

When swimming, the fore limbs are folded back against the sides, the tail only being used as a means of propulsion. Several of the larger iguanas, such as the common or tuberculated

Photo by W. Saville-Kent, F.Z.S.] [Milford-on-Sea.

AUSTRALIAN WATER-LIZARD.

This lizard is of aquatic habits, and runs on its hind legs when traversing long distances.

Photo by W. Saville-Kent, F.Z.S.] [Milford-on-Sea.

AUSTRALIAN WATER-LIZARD.

Showing attitude when running.

of the World570 The Living Animals

species, attain to a considerable length, 5 or 6 feet; their bodies are proportionably thick, and the white flesh, in this last-named is highly variety more particularly, esteemed as a table delicacy. The common TUBERCULATED IGUANA is an essentially handsome species, its skin being variegated with bands and shadings of brown and green, which are lightest and brightest in the males and younger individuals; the neck and snout F.Z.S.] Photo by W. Saville-Kent, (Milfo,-d-o-,i-Sca. and jaws are decorated with pro- JEW OB BEARDED LIZARDS. AUSTRALIAN rounded tubercles; a large,The scales of the bearded lizard are exceedingly rough and sharp, sometimes cutting the skin jecting, of those who handle them incautiously. baggy, dewlap-like membrane, capable of inflation at the animal's will, depends from the chin and throat; and a deeply serrated crest of elevated scales extends from behind the head, down the centre of the back, nearly to the extremity of the tail. The Iguana Family includes a species with essentially marine proclivities, this being the GALA- PAGOS SEA-LIZARD. This animal was first discovered to science by the late Mr. Charles Darwin, who Photo by W. Saville-Kent, F.Z.S.] [Milford-on-Sea.

BEARDED LIZARD.

With its beard-like throat-membrane fully expanded.

found it in considerable numbers on the shores of the islands which constitute the Galapagos group. The lizards were observed to spend much of their time swimming in the sea, but at no very great distance from the land. Experiments proved that they could live for a very considerable interval entirely submerged, examples sunk with weights for as much as an hour emerging entirely unaffected from the ordeal. While the Iguanas may be described as essentially American, one or two exceptional forms are found inhabiting the relatively remote regions of the Fiji Islands and Madagascar. The so-called FIJI BANDED IGUANA (photographs of a pair of which, once in the writer's possession, are reproduced is on page 575) is a very beautiful creature. The body shapely and well proportioned, and terminates in a tail of abnormal length equal to quite twice that of the body the entire dimensions measuring some 3 feet. The male is

Milfortl-on-Sea. much more bright in hue than the female; for while the Photo by W. Saville-Kent, F.Z.S., latter is usually of a uniform light green throughout, the A YOUNG BEARDED LIZARD. its habitual sleeping attitude. male is variegated, with broad, alternating bands of brightest Showing

Photo by W. Saville-Kent, F.Z.S., Milfortl-on-Sea. A YOUNG BEARDED LIZARD. Showing its habitual sleeping attitude.

Lizards 571

emerald-green and pale French grey. Around the lips and eyes there are lines of brightest yellow, and the throat is almost pure white.

The small group of GIRDLE-TAILED LIZARDS belongs exclusively to the African and Madagascar regions, its typical representative being the Cape and Orange Eiver Colony species, illustrated on page 575. The symmetrical whorls of long, spinous scales encircling the tail in this and the allied forms constitute a prominent feature, and have originated the popular name of Girdle-tails.

The most aberrant representatives of the Lizard Tribe, with regard to one very important characteristic, are undoubtedly the two species of HELODERM, or "SiLATiCA," as they are called by the natives. These reptiles (page 576) occupy the unenviable position of 1'hoto by W. Saville-Kent, F.Z.S.] [Milford-on-Sea. being the only known lizards which possess AUSTRALIAN YORK OR MOUNTAIN-DEVIL. poisonous properties, their bite having been A spinous lizard which inhabits the avid plains of Central Australia. demonstrated to be fatal to smaller mammals, and to be attended by very serious symptoms in the case of human subjects being bitten. itThe more common MEXICAN HELODERM has been in residence at the Zoo for many years; attains to a length of from 18 to 20 inches, and its stout, squat body, short limbs, warty skin, and peculiar colouring are calculated at first sight to awaken a feeling of revulsion in the beholder. Like the wasp, the salamander, and other animals whose conspicuous tints indicate their poisonous or other baneful properties, the heloderm is distinguished by a lurid ground-colour, varying in individuals from yellow-orange to flesh-pink, upon which are superimposed bold, network-like markings of blue-black or dark brown tints. Along the tail these reticulations usually take the form of more or less irregular rings. 1 Although the heloderms possess such deadly properties, those at the Zoo manifest a by no means aggressive disposition, and allow their keeper or even strangers to handle them with impunity. In experiments purposely made to substantiate or refute the previously current rumours as to the poisonous nature of these animals, two guinea-pigs succumbed to bites received in the course of the day. The owner of the reptiles, who was also bitten on one occasion through incautiously handling, suffered very severe, though happily not fatal, effects. In connection with its poison-dealing properties it is found that it possesses certain long and fang-like teeth, which are set loosely in the jaws, and which have grooves before and behind for the transmission of the poison, Photo by w. saviiu-Kmt, F.Z.S.'] which is secreted by special glands situated SPINOUS LIZARD, OR MOUNTAIN-DEVIL. close to their base. The favourite habitat Of This species feeds exclusively upon ants.

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