Page:Encyclopædia Britannica, Ninth Edition, v. 14.djvu/760

 736 LIZARD anolis possess the power of changing their colours in a most extraordinary degree, the brilliant iridescent hues of their body passing almost in an instant into a dull sooty brown in an irritated or alarmed animal. They are much fed upon by birds and snakes, and have, like all small much-persecuted lizards, a fragile tail, easily reproduced. They bring forth only one large egg at a time, but probably breed several times during the season. The third iguanoid, Phrynosoma, is a terrestrial form. Several species are known, inhabiting the plains of south western America and Mexico. Since the opening of the Pacific Railway, living specimens are frequently sent to Europe, and sold under the name of &quot; Californian toads.&quot; Although they belong to the same family, a greater con trast than that between the nimble, slender, and long- tailed Anolis and the toad-like Phrynosoma can hardly be imagined. The body is short, broad, and depressed, end ing in a short tail, covered with rough tubercles or spines; the short head is armed behind with long bony spikes; the colours are a motley of brown, black, and yellow. Their defence against birds lies chiefly in their outward appearance, as, whilst they rest quiet, they are difficult to distinguish from a stone overgrown with lichen ; nor have we ever found their remains in the stomach of snakes, their spines proving a sufficient protection against these equally formidable enemies. They are said to move with rapidity in a wild state, but in confinement, especially when the animal believes itself observed, their movements are extremely sluggish and their manners uninteresting. It seems to be a common belief in California that they have the power of squirting a blood-red fluid from the corner of the eye to some distance ; but nothing has been found, on anatomical examination, to establish the correct ness of this assertion. They attain a length of from 6 to 8 inches. Of the Agamiclx, which represent the iguanas in the Old World, and which have been differentiated into a still greater number of distinct generic forms, several genera deserve more than a merely nominal notice. The perhaps most highly specialized form are the Dragons (Draco), a genus of small lizards from the East Indies, more common in the archipelago than on the continent, but absent in Ceylon. The character by which they are at once recog nized is the peculiar additional apparatus for locomotion, formed by the much-prolonged five or six hind ribs, which are connected by a broad expansible fold of the skin, the whole forming a subsemicircular wing on each side of the body. The snakes are the only order of vertebrates in which the ribs serve as organs of locomotion, but, whilst in that order all the ribs are charged with a function for which no other special organ exists, in the dragons only a part of the ribs are modified for the purpose of assisting four well-developed limbs. The dragons are tree-lizards; they take long flying leaps from branch to branch, supported in the air by their expanded parachutes, which are laid backwards at the sides of the animal while it is sitting or merely running. If the hind or fore limbs of a dragon were cut off, it would be helpless, and deprived of locomotion, but it could continue to move with velocity after the loss of its wings. Like the anolis, whose analogues they are in the Old World, they are provided with long highly ornamented dewlaps. These appendages are found in both sexes, one in the middle and one on each side of the throat, but they are much more developed in the mature male. The tail is very long and slender, not fragile; we have never seen a dragon in which this member was mutilated ; it seems to be necessary for their peculiar locomotion, and probably its loss soon proves fatal to the animal. Cantor says that the l transcendent beauty of their colours baffles description. ; As the lizard lies in the shade along the trunk of a tree, its colours at a distance appear as a mixture of brown and grey, and render it scarcely distinguishable from the bark. Thus it remains with no signs of life except the restless FIG. 4. Dragon (Draco teenioplerus), eyes watching passing insects, which, suddenly expanding its wings, it seizes with a sometimes considerable unerring leap. All the species attain a length of 7 or 8 inches, of which the tail takes at least one half. They deposit three or four eggs at a time. Calotes is another genus of agamoids peculiar to the East Indies ; it comprises numerous species well known in India by the name of &quot; blood-suckers,&quot; a designation the origin of which cannot satisfactorily be traced. They are tree-lizards, extremely variable in their colours, which change, not only with the season, but also at the will of the animal. The males, and in some species also the females, possess a crest of compressed scales along the back. Of the Australian agamas no other genus is so numerously represented and widely distributed as Gram- matophora, the species of which grow to a length of from 8 to 18 inches. Their scales are generally rough and spinous ; but otherwise they possess no strikingly distin guishing peculiarity, unless the loose skin of their throat, which is transversely folded and capable of inflation, be regarded as such. On the other hand, two other Australian agamoids have attained some celebrity by their grotesque appearance, due to the extraordinary development of their integuments. One (fig. 5) is the Frilled Lizard (Chlamy- dosaurus), which is restricted to Queensland and the north coast, and grows to a length of 2 feet, including the long tapering tail. It is provided with a frill-like fold of the skin round the neck, which, when erected, resembles a broad collar, not unlike the gigantic lace-collars of Queen