PSAMMOPHIS. 381 



Cerberus, Cuvier. 



Head of moderate length and widtb. Body cylindrical, its hinder 

 part and the tail rather compressed. Cleft of mputh wide, turned 

 upwards behind. Eye small. Pupil vertical. Snout covered with 

 shields. Occiput with scales. Nostrils between two nasals, the anterior 

 of which is larger, forming a suture with the corresponding nasal of the 

 other side ; two small triangular anterior frontals. Eye surrounded 

 by a ring of small orbitals. Posterior upper labials divided transversely 

 into two. Scales keeled in from 21 to 25 rows. Ventrals 132-148. 

 Anal bifid. Sub-caudals two-rowed, 54 to 57. Maxillary teeth in a 

 continuous series, slightly increasing in length posteriorly, the last 

 being grooved. Mandibular teeth longest in front. Viviparous. 



Cerberus rhynchops, Russell, Ind. Serp. ii. p. 43. pi. 40 ; 'id. i. pi. 

 17; Gunth. Rep. Br. Ind. p. 279; Theoh. Cat. Rep. Br. Ind. p. 185. 

 Hydrus rhynchops, Schn. Hist. Amp. i. p. 246. Cerberus boseformis, 

 n. et B. vii. p. 978. 



The two anterior frontals together are as large as one of the pos- 

 terior. Vertical elongate, generally broken up into smaller shields, 

 sometimes perfect. Loreal as large as, or larger than, the post-ocular 

 extending on to the upper surface of the snout. One pr£e-ocular 

 sometimes divided ; two post-oculars, one infra-ocular ; nine or 

 ten upper labials, the fifth below the infra - o cular ; some (2 to 4) of the 

 hinder ones split transversely into two. Temporals scale-like. Three 

 pairs of chin shields, of which the anterior are the largest, broadest in 

 front and tapering behind ; the second and third pairs wedged in 

 between the front pair and the lower labials. Upper parts blackish ash, 

 with irregular black cross bars ; the two or three outer series of scales 

 yellowish. Lower parts whitish, with more or less confluent dark 

 blotches. Labials black-spotted. 



Hob. — The Sind and Mekran Coasts and the Coasts of India and 

 Burmah, also the Malayan Peninsula, the Andamans and Nicobars. 

 Attains to a length of 48 inches. 



Family, PSAMMOPHIDiE. 

 Desert Snakes. 



Body and tail generally elongate. Head distinct from neck. Loreal 

 region very concave. Scales smooth, in 15-19 rows. Sub-caudals two- 

 rowed. Cleft of mouth wide. Nostril lateral. Eye moderate. Pupil 

 round or vertical. Head shields normal. Posterior frontals rounded or 

 angular behind. Vertical nai-row. Superciliaries prominent. Loreal 

 present. One praa and two post-oculars. One of the maxillary teeth 

 longer than the others ; the last grooved. 



Psammophis, Boie. 



Head rather long and pointed. Vertical long and narrow. Loreal 

 elongate. Scales lanceolate, smooth, in 15-19 rows. Anal bifid. Pupil 

 round. Front teeth of lower jaw long. 



