17 



The parietals are always more or less broken up 

 into scales. 



The nasals are large and in contact behind the 

 rostral. They are semi-divided, the cleft ex- 

 tendino from the nostril to the 1st or 2nd 

 upper labial. 



Small internasals are present, also a loreal. 



One, two or three sub-oculars. 



Nine or ten upper labials, the posterior divided 

 transversely. 

 Scales — 23 or 25, very strongly keeled. 

 Fen«ra/5— Narrow, and rounded, 132 to 160 ; anal divid- 

 ed, Sub-caudals 49 — 72. 

 Colour — Grey, brown, olive, dark ash or blackish above. 

 More or less distinct darker spots or cross- 

 bars, especially posteriorly. A black streak 

 on each side of the head, passing through the 

 eye. A more or less distinct white or yellowish 

 lateral band. 



Beneath whitish or yellowish, spotted or barred 

 or marbled with dark ash or black, or almost 

 entirely black. 

 ffahitat— Common in East Indian estuaries. 



GROUP III. — Snakes with broad ventrals 

 and shielded heads. 



Sub-Group a. — Harmless. 



THE BLUNT-HEADED SNAKE (Amhlycephalusmonticola). 



Note. — The whole family of snakes, to which this one 

 belongs, is characterised by the absence of a " mental groove." 

 The mental groove, which exists in nearly all other snakes, 

 is a groove running longitudinally along the chin between 

 the sub-linguals or chin shields — {vide Fig. 3, a to b.) 



