12. GONTOCEPHALTTS. 283 



II. Supraciliary border normal. 



A. Enlarged scales scattered among tlie dorsals. 



1 . Nuclial and dorsal crests continuous. 



a. Ventral scales perfectly smootli. 



5. liogaster, p. 286. 

 I. Ventral scales feebly keeled. 

 Enlarged dorsal scales forming a 

 lateral series ; none scattered on the 



sides 6. miotynvpanum, p. 287. 



Enlarged dorsal scales irregularly 



scattered 7. lorneensis, p. 288. 



c. Ventral scales strongly keeled. 



Gular scales smooth 8. hellii, p. 288. 



Gular scales strongly keeled 9. sophicej^. 288. 



2. Nuchal crest strongly separated from the dorsal. 



a. Ventral scales keeled. 



Enlarged dorsal scales forming a 



regular lateral series parallel to the 



dorsal crest 10. semperi, p. 289. 



Enlarged scales forming irregular 



vertical series on the flanks ; tym- 

 panum smaller than the eye-opening . . 11. inter ruptus, p. 290. 

 Enlarged scales scattered or forming 



vertical series ; tympanum quite as 



large as the eye-opening ; a high 



caudal crest 12. dilophus, p. 290. 



b. Ventral scales smooth 13. tuherculatus, p. 291. 



3. Nuchal and dorsal crests suhcontinuous. 



Limbs above with unequal-sized scales, 



the largest being spinose 14. spinipes, p. 292. 



Limbs above with subequal scales ; the 

 longest spines of the nuchal crest 

 shorter than the greatest diameter 

 of the tympanum 15, subcristatus, p. 292. 



Limbs above with unequal scales; nu- 

 chal crest much higher than dorsal . . 16. Tiuniii, p. 293. 



B. No enlarged dorsal scales. 



1. Ventral scales keeled. 



a. No strongly enlarged scales below the ear. 



Nuchal crest very low, reduced to a 

 few widely separated, triangular lobes ; 

 dorsal crest indistinct 17. modestus, p. 294. 



