SCALED REPTILES LIZARDS. 399 



aspect of the body are likewise not enlarged. Many of the species develop 

 large ornamental crests or pouches, either in both sexes or in the male alone. 

 These lizards generally have a long tail, which is not brittle ; and they always 

 possess well-developed fore-limbs, which, with one exception, are five-toed. 

 As a rule, the teeth are unequal in size, those at the corners of the jaws being 

 developed into tusks. As in other lizards, the arboreal species have com- 

 pressed bodies, while in those that 

 dwell on the ground the trunk is 

 more or less depressed. Although, as 

 already said, agamoids are widely spread 

 in the Old World, they attain their 

 maximum development in the Oriental 

 countries, only three generic groups 

 inhabiting Africa. Perhaps the most 

 remarkable members of the family are 

 the flying lizards (Draco) of the Oriental 

 countries, in which the hinder ribs are 

 expanded to support a kind of para- 

 chute-like expansion of the skin of the 

 flanks. These folds can be closed in a Fig - i2.-Fi.YiNG LIZARD (Draco volans) 

 fan-like manner, and there are other 



expansions on the throat. The entire body is much depressed, and the 

 tail is very long and tapering. The coloration of the upper surface of 

 the body is metallic, with dark spots and bands, the parachute of the 

 common species being bright orange with black markings. These lizards 

 live high up on the trees, and pass from bough to bough by taking 

 flying leaps with the support of the parachute. At times the expansions 

 of skin on the throat are erected. The Oriental region is likewise the 

 home of the beautiful tree-lizards of the genus Calotes, which are also 

 thoroughly' arboreal, although unable to take flying leaps. They have the 

 drum of the ear visible externally, a crest running down the neck and back, 

 the large keeled scales on the back of equal size, a long, whip-like tail, and 

 no distinct fold of skin on the throat. Many of them have the power of 

 rapidly changing their brilliant colours, and some measure as much as 

 sixteen inches in length. More curious are the arboreal horned lizards 

 (Ceratophora) of Ceylon, easily recognised by the presence of a horn on the 

 nose of the males, and sometimes also in the females. There is_ no crest on 

 the neck, and the drum of the ear is concealed. Next on our list are the 

 numerous species of the typical genus Agama, which range from South- 

 Eastern Europe over South-Eastern Asia, although absent from the greater 

 part of India and Ceylon. These lizards are terrestrial in their habits, and 

 accordingly differ from all the foregoing, with the exception of the flying- 

 lizard, in having the body markedly depressed. They have the drum of the 

 ear exposed, large thickened scales in front of the vent in the males, a fold of 

 skin across the throat, and a pit on each side of the same part, while if the 

 back is furnished with a crest, this is of small size. Jn parts of Asia these 

 lizards are some of the most common representatives of their tribe, and may 

 be seen in hundreds basking in the sun. 



Many of the genera of lizards are far from easy to distinguish from one 

 another, but there is no difficulty in recognising the extraordinary Australian 

 frilled lizard (Chlamydosaurus kingi), which has the throat surrounded by a 

 large frill-like expansion of skin extending on to the sides of the neck. 



