CLASS REPTILIA 537 



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



Fig. 45 2 )- 



Family i. CHAM^LEONTID.^:. - - CHAMELEONS. - With 

 characters of the suborder. Examples: Chamcdcon 

 (Fig. 452), Brookes ia, Rliampholeon. 



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 i . 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), Gonyccphalus, Calotcs. 



Family 3. IGUANHXE. -- NEW-WORLD LIZARDS. SAURIA 

 resembling AGAMID^E, but usually with teeth similar 

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

 Examples: Anolis, Scdoporus, 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: Heloderma(Fig.4$g). 



Family 6. VARANID.E. MONITORS. SAURIA with tongue 

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

 limbs well developed. Example: Varanus. 



