10. TROPIDONOTUS. I'Jo 



2. Scales in 19 rows, 



a. Usually a single anterior temporal. 



a. Usually 7 upper labials, third and fourth entering 

 the eye. 



Ventrals 157-190 18. natrix, p. 219. 



Ventrals 127-151 19. vibakari, p. 221. 



/3. 8 or 9 upper labials, three entering the eyo. r^ 222 

 Ventrals 138-147 ; subcaudals 40-53 .... 20, conspiciUatus, 

 Ventrals 1G3-175 ; subcaudals 73-95 .... 21. 2^»>'aIleh(S, p. 223. 

 Ventrals 150-154 ; subcaudals 80-100 . . 22. khasiensis, p. 223. 



b. Two anterior temporals ; 9 upper labials, fourth to sixth 



entering the eye. 



Frontal once and a half to once and three [p. 224, 



fourths as long as broad 23. trianguligervs. 



Frontal once and one third as long as broad. 24. petersli, p. 225. 



II. Maxillary teeth not more than 30, the hinder gradually enlarged ; 

 eyes rather small and, like the nostrils, directed upwards and 

 outwards ; internasals usually much narrowed in front. 

 (Nekodia.) 



A. Anal single ; a single anterior temporal ; scales in 19 



^«^^- ^ [p. 225. 



Scales strongly keeled 25. melanogaster. 



Scales smooth 26. Icevissimus, p. 226, 



B, Anal divided. 



1, Scales smooth or feebly keeled, in 17 or 19 rows. 



Scales smooth, in 19 rows ; a single ante- 

 rior temporal 27, oUvacem, p, 227. 



Scales smooth or faintly keeled, in 17 rows; 



a single anterior temporal 28. pygcns, p, 228, 



Scales smooth or faintly keeled, in 17 rows ; 



two anterior temporals 29, jmnctidatus, p. 228. 



Scales feebly keeled, in 19 rows ; three labials 



entering the eye 30. modesfits, p. 228. 



Scales feebly keeled, in 19 rows; one or [p. 230. 



two labials entering the cj-e 31. sancti-johannis, 



2, Scales in 19 rows, strongly keeled; usually two anterior 



temporals ; 4th, 5th, or 4th and 5th labials entering the 

 eye; ventrals not more than 161. 



Scales of 2 or 3 outer rows smooth 32. piscator, p. 230. 



2 



