89 



Z. NIGROMAEGINATUS, Blyth. 



Scales 16, elongate and pointed, the 4 median rows keeled, 

 others with apical grooves. Ventrals 193,subc. 126. Green 

 above, paler below, with 2 posterior broad black stripes. 

 Himalayas. 



HERPETOEEAS, Gunther. 

 Body slender, compressed; head elongate, rounded in 

 front. Eye moderate. Scales elongate, 17 or 19 ; ventrals 

 bent up at the sides, above 200 ; anal bifid. One preocular, 

 head-shields regular. Last tooth the longest. 



H. siEBOLDii, Othr. 



Scales 19, slightly keeled. Ventrals 216, subc. 90. Loreal 

 single. Labials 8 (3, 4 and 5). Greenish brown, belly yel- 

 lowish. 



Himalayas. A solitary museum specimen. 



An ill-described snake called Coluber prasinus by Mr. 

 Blyth, perhaps belongs to the above species. There is some 

 reason to consider that the genus is a refuge for aberrant 

 young specimens of Ptyas mucosus. I named three such 

 specimens of this snake Herpetodryas prasinus, and did 

 not see my mistake for a long time, though its possibility 

 was pointed out to me by Dr. Gunther. 



Group IV.— NATRICINA. 



These snakes lead off to the Homalopsidse ; they are 

 ground-snakes, but many of them frequent the water, and 

 have the nostrils rather superior. Scales always more or 

 less keeled ; ventrals considerably less than 200, anal bifid. 



TROPIDONOTUS, Kuhl. 

 Body rather stout, head distinct from the neck, gape wide. 

 Eye moderate. Scales generally 17-19, keeled, especially 

 towards the tail. Teeth numerous, increasing. 



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