84 REPTILES. 
d. Scales keeled ; labial shields not pitted ; nostrils in a sin- 
gle plate. Asia. 
16. Enycrus. Head covered with small irregular shields ; nostrils 
in a single plate. Asiatic Islands. 
17. Casarea. Head scaly; muzzle covered with symmetrical 
shields ; nostrils in a single plate ? 
18. Botyeria. Head covered with symmetrical shields ; nostrils in 
a single plate. 
I]. Tail very short, slightly or not prehensile. Head indistinct, 
short. 
a. Head covered with scales; pupil oblong ; scales convex ; 
subcaudal shield one-rowed ; intermaxillary teeth none ; 
supra-orbital bone none. Erycina. 
19. Cusorta. Muzzle rounded ; ventral and subcaudal plates nar- 
row; scales ovate, of body and tail smooth. 
20. Goneytopuis. Muzzle wedge-shaped ; jaws equal; head with 
small keeled scales; scales of back keeled ; body fusiform. 
21. Eryx. Muzzle wedge-shaped ; upper jaw largest; head with 
small scales; scales of back smooth, of hinder part of body 
keeled. 
22. CLrotHonta. Muzzle wedge-shaped; upper jaw largest ; scales 
smooth. 
b. Head shielded ; pupil round. 
* Nostrils in a single shield ; eyes surrounded by shields ; intermax- 
illury teeth none. Cylindrophina. 
23. CyLINDROPHIS. 
** Nosirils between two shields ; eyes surrounded by small scales. 
Charinina. 
24. CHARINA. 
*** Nostrils between two shields ; eyes in a single shield ; intermax- 
illary teeth distinct ‘Tortricina. 
25. Torrrix. 
