12 



REPTILE GALLERY. 



of rare beauty and variety of colour, and forming a striking contrast 

 to the species of Phrynosoma (Case 19) of North America and 

 Mexico, which, on account of their shape and sluggish habits, have 

 earned the name of Horned or Californian Toads (fig. 6). 

 [Case 22.] The Agamidcs represent the Iguanas in the Old World. They 

 are distinguished by the acrodont dentition, the teeth being anky- 



Fig. 7. 



Lower jaws, showing the acrodont (a) and pleurodont (b) dentition. 



losed to the upper edge of the jaws, an arrangement which occurs 

 also in the Rhynchocephalians, some Amphisbaenians, and the 

 Chamseleons. Lizards of this family are most abundant in the 

 Indian and Australian regions, showing a great variation of form 

 analogous to that of the preceding family. The perhaps most 

 highly specialized Agamoid is the genus Draco, small winged Lizards 

 from the East Indies (fig. 8). The Dragons are tree-lizards, and 

 possess a peculiar additional apparatus for locomotion : the much- 

 prolonged five or six hind ribs are connected by a broad expansive 

 fold of the skin, the whole forming a subsemicircular wing on each 

 side of the body, by which they are enabled to take long flying 

 leaps from branch to branch, and which are laid backwards at the 

 sides of the animal while it is sitting or merely running. 



The Frilled Lizard (Chlamydosaurus kingii) is an Australian 

 Agamoid, growing to a length of two feet. It is provided with a 

 frill-like fold of the skin round the neck, which, when erected, 



