332 TEIIDZ, 
Tail not or but feebly compressed ; dorsal scales small, uniform. 
1. Tupinambis, p. 334. ~ 
Tail strongly compressed, with a double longitudinal keel above ; 
dorsal scales intermixed with large keeled tubercles. 
2. Dracena, p. 337. -~ 
2. Ventral plates large, forming less than 20 longitudinal 
series. 
Ventral plates keeled ; femoral pores. 
3. Centropyx, p. 339. 
Ventral plates keeled; no pores .. 4. Monoplocus, p. 343. 
Ventral plates smooth .......... 5. Ameiva, p. 343. 
B, Scaly portion of the tongue arrow-headed, bifid and not re- 
tractile posteriorly. 
1. Tail rounded. 
a. Teeth longitudinally compressed. 
Head-shields large, regular ; ventral shields in less than 20 longi- 
tudinal rows .. 1... cee cece eee 6. Cnemidophorus, p. 360. 
Head-shields small, numerous; ventral shields in more than 20 
longitudinal rows ............ 7. Callopistes, p. 375. 
6. Teeth transversely compressed. 
POSS AVOiy states worden aia 8. Dicrodon, p. 377. 
Toes four. sie asese bea e se eek 9. Teius, p. 378. 
2. Tail strongly compressed, bicarinate. 
Dorsal scales small, uniform...... 10. Crocodilurus, p. 380. 
II. Nasal plates widely separated by one or two frontonasals ; 
fingers and toes five, all clawed. 
A. Prefrontals present. 
1. Tail compressed, with a double denticulated crest. 
Dorsal lepidosis composed of small scales intermixed with large 
keeled ones.............00-55 11. Neusticurus, p. 381. 
2. Tail round or cyclo-tetragonal. 
a. Lingual papille, oblique plice. 
Dorsal scales large, pointed, strongly keeled. 
12. Alopoglossus, p. 383. 
