252 OPHIDIA. 



ZAMENIS, Wagler. 



Body and tail elongate ; trunk with 200 or more ventral shields ; head 

 distinct from neck, flat ; eye of moderate size, with round pupil ; nostril 

 lateral, between two plates. The shields of the head have a tendency to 

 divide in two or more pieces ; loreal present ; generally two anterior and 

 two posterior oculars ; eye sometimes surrounded by separate pieces of 

 the upper labials. Scales smooth or slightly keeled ; ventrals rounded or 

 with a very indistinct lateral keel ; anal bifid ; subcaudals two-rowed. Teeth 

 numerous in the jaws and on the palate ; the last maxillary tooth is generally 

 the largest, and separated from the others by a short interspace. 



This genus of Colubrine snakes is confined to the countries round the shores of the Medi- 

 terranean, extending eastwards through South-western Asia to the peninsula of Southern 

 India; it is distinguished from the other Colubri by its dentition, which cliaracter, however, 

 becomes rather indefinite in Z. diadema and also in Z. fasciolatus ; the British INIuseum 

 possesses an example of the former and two of the latter in which the dentition is corypho- 

 dont or even isodont. 



The following species occur in British India : — 



A ring of small separate shields round the orbit ; a transverse series of small 



shields between posterior frontals and vertical Z. diadema, p. 252. 



Scales in nineteen rows ; occipitals truncated behind, each with a small semi- 

 circular shield behind Z. ventrimaculatus, p. 253. 



Scales in twenty-one rows ; a series of large round brown spots along the 



anterior half of the back Z. gracilis, p. 254. 



Scales in twenty-one or twenty-three rows ; narrow white, broAvn, or black 



variegated cross bands on the anterior part of the back Z. fasciolatus, p. 254. 



Zamenis diadema. (Plate XXI. fig. G.) 



Russell, ii. p. 34. pi. 30. 



Coluber diadema, Schleg. Phys. Serp. ii. p. 148 (not Blyth). 



Closely allied to Z. cliffordii. Head rather elongate, broader behind, very distinct from 

 neck. Body and tail rather slender, compressed. Eye of moderate size. Rostral shield as 

 high as broad. Anterior frontals rather larger than posterior, which are separated from the 

 vertical by a transverse series of four small shields. Vertical large, five-sided ; occipitals 



