. 
— 
COLUBRLN & 179 
*** Scales keeled; loreal and prefrontal entering the 
eye. 
T Scales not striated ; pupil round. 
A pair of internasals ............ 19, Amphiardis, p. 290. 
A single internasal ............ 20. Haldea, p. 290. 
tf Scales striated; pupil subelliptic 
A pair of internasals ............ 21. Streptophorus, p. 291. 
**** Scales smooth. 
+ Loreal and preocular present. ~ 
Nostril an oblique slit between two nasals ; pupil round. 
23. Hydrablabes, p. 296. 7 
Nostril between two nasals ; pupil bags subelliptic. 
Trachischium, p. 297. 
Nostril in a semidivided nasal ; We vertically subelliptic. 
25. Rhabdops, p. 300. 
tt No loreal; a large semidivided nasal in contact 
| with a preocular. 
Dorsal scales oblique ...........- 26. Plagiopholis, p. 301. 
+tt Loreal and prefrontal entering the eye. 
Maxillary teeth 30 to 35 ; pupil args subelliptic. 
27. Oxyrhabdium, p. 302. 
Maxillary teeth 20 to 25; pupil round. 
28. Xylophis, p. 303. 
t+ttt No loreal; a single small nasal; 
present or absent. 
Maxillary teeth 20 to 22; pupil rete subelliptic. . 
29. Brachyorrhus, p. 305. 
p. Maxillary bone not extending forwards beyond the 
palatines; scales keeled; loreal and prefrontal 
entering the eye. 
Maxillary teeth about 10 ; scales ees a single prefrontal. 
Chersodromus, p. 295. 
Maxillary teeth about 20 ; scales Beta a pair of prefrontals. 
30. Elapoides, p. 306. 
b. Labial shields not entering the nostril; subcaudal shields 
single. 
Beales kegled ............seecee $1. Achalinus, p. 808, 
N 
