6 REPTILES. 



Suborder I. Slender-tongued Lizards, (Leptogloss^). 



Tribe I. Cyclosaura. 



Scales of the belly square (very rarely rhombic, keeled), in cross 

 bands ; of the back and tail rhombic, imbricate, or circular and 

 subgranular, placed in cross rin,s:s; of the sides generally granular, 

 rarely like the back. Tongue elongate, flattened, base sometimes 

 sheathed, generally free, only attached to the gullet by a long fre- 

 num, end with 2 elongate, cylindrical, horny tips. Tail elongate, 

 with whorls of scales, generally conical, tapering, sometimes com- 

 pressed, with 2 elevated crests above. 



A. Head ivitk small many-sided shields. Tongue sheathed dft the 

 base. Sides Jiattish^ granular. ■ 



Family I. Monitors, (Monitorid^). 



Head with minute polygonal shields. Teeth adnate to the in- 

 ner side of the jaws. Tongue elongate, slender, retractile into a 

 sheath at its base. Scales small, roundish, placed in cross rings ; 

 those of the sides like those of the back. Legs 4, strong. Toes 

 5-5, compressed, unequal. Thighs poreless. Superorbital plate 

 bony. Old world, near water. 



Synopsis of the Genera. 



A. Tail roundj without any keel above. 



1. PsAMMOsAURUs. Nostrils large, oblique, near the eyes. 



2. Odatria. Nostril moderate, longitudinal, near the apex of 



muzzle. 



B. Tail compressed, with a keel formed of 2 rows of scales above. 



3. Regenia. Nostrils large, oblique, near the eyes. Toes short. 



4. Empagusia. Nostrils large, oblique, anterior. Toes short. 



5. Uaranus. Nostrils oblong, longitudinal, subcentral. Toes 



elongate. 



6. Monitor. Nostrils round, subcentral. 



7. Hydrosaurus. Nostrils round, anterior. Teeth small. 



