On a new Snake from Xorthern China. 243 



XXT. — DeacrijAwn of a new Snake of the Genus Coluber 

 from yorthern China. By G. A. BOULENGER, F.K.S. . 



(Published by permissioo of the Trustees of the British Museum.) 



Two years ago I described in these ' Annals ' (xiii. 1914, 

 }', 57Gj a new and very distinct species of Coluber discovered 

 by Mr. A. L. Hall at Chilifeng, N.E. Cliilili Province, which 

 I named (.'. halli. Mr. Hall has since been so kind as to 

 send a second series of snakes from the same locality, and 

 this includes, in addition to five further specimens of C. halli, 

 a single specimen of another species which I regard as new 

 and of which I here offer a description. 



The uddiiiunal specimens of C. halli show the following 

 vaiiaiion in the nunjber of scales and shields : — 



S 23 scales. 172 ventrals. 69 subcaudals. 



$ 25 „ 181 „ 63 „ 



V 23 „ 179 „ 64 „ 



"^'g 23 „ 171 „ 05 „ 



„ 23 „ 171 „ 69 



The formula for the seven known specimens is therefore — 



Sc. 23-25. V. 171-181. A. 2. C. 58-69. 



Coluber a no mains. 



Snout rounded, scarcely prominent ; canthus rostralis very 

 obtuse, loreal region slightly concave ; eye rather small, one- 

 third length of snout, llostral much broader than deep, just 

 visible from above ; internasals as long as broad, as long as 

 the praifrontals ; frontal as long as broad, two-thirds its 

 distance from the end of the snout, three-tifths the length of 

 the parietals ; lureal longer than deep; piaeociilar single, 

 no subocular below it ; two postoculars ; temporals 2 + 3 or 4 ; 

 scv en upper labials, third and fourth entering the eye ; four 

 luwer labials in contact with the anterior chin-shields, which 

 aie a little longer than the posterior. Scales in 22 rows, 

 dorsals feebly but very distinctly keeled, laterals smooth. 

 Ventrals not angulate laterally, 212; anal divided; sub- 

 caudals mostly single, G5. Dark brown above; a large 

 blotcii on the neck and a streak behind the eye black ; hinder 

 part of body and tail with rather irregular black cross-bars; 

 lower parts white, with greyish spots anteriorly ; subcaudals 

 eiliied with blown. 



