CLASS REPTILIA 537 



digits in groups of two and three, for grasping (see 



Fig. 45 2 )- 



Family 1. Chaivleleonttd.s:. — Chameleons. — With 

 characters of the suborder. Examples: Chamceleon 

 (Fig. 452), Brookesia, Rhampholeon. 

 Suborder 2. Sauria (Lacertilia). — Lizards. — Squamata 

 with transverse anal opening; paired copulatory organs; 

 at least a vestige of a pectoral arch; usually well- 

 developed limbs ; rami of lower jaw united. (Only ten 

 of the twenty families are listed below.) 



Family 1. Geckonid^e. — Gecko. — Sauria with four legs; 

 eyes usually without movable lids; tongue protrusible; 

 many with adhesive digits for climbing. Examples: 

 Gecko (Fig. 453), Gymnodactylus, Sphcerodactylus. 



Family 2. Agamid^e. — Old-world Lizards. — Sauria 

 with well-developed limbs; eyes with complete lids; 

 tongue broad and short; teeth usually differentiated 

 into incisors, canines, and molars (heterodont), and 

 always situated on the edge of the jaw (acrodont). 

 Examples: Draco (Fig. 454), Gonycephalus, Calotes. 



Family 3. Iguanid^e. — New- world Lizards. — Sauria 

 resembling Agamid^e, but usually with teeth similar 

 (homodont) and fastened in a groove (pleurodont). 

 Examples: Anolis, Sceloporus, Phrynosoma (Fig. 457), 

 Iguana (Fig. 456). 



Family 4. Anguid^e. — Old and New-world Lizards. 

 Sauria with teeth in a groove; anterior part of tongue 

 thin, and retractile into posterior part; limbs present 

 or absent; body protected by bony plates. 



Family 5. Helodermatid^e. — Beaded Lizards. — Sauria 

 with grooved teeth; poisonous; tongue bifid, protractile; 

 limbs short but strong. Examples : Hcloderma (Fig. 459). 



Family 6. Varanid^e. — Monitors. — Sauria with tongue 

 long, smooth, deeply bifid and retractile; tail long; 

 limbs well developed. Example: Varanus. 



