SNAKES OF OHYLON. 335 



Genus PORRECTICOLLIS Gen. nov. 

 (Latin " porrectus " stretched, " collis " neck.) 



General Characters. — Length moderate. One of the five 

 very slender-necked species ; the diameter anteriorly one- 

 third to one-fifth that of the extreme depth posteriorly. 



Cranial Osteological Characters.^ — Nasals : Sutured to prse- 

 f rentals and frontal ; longer than frontal. Prsefrontals : Meet- 

 ing parietal, but not postfrontals. Frontal : As broad as long ; 

 not meeting postfrontal at rim of orbit. Parietal : Not keeled 

 interiorly. Quadrate : Vertical ; extreme length superiorly 

 equal to its own depth. Maxilla : Not extending beyond 

 palatine anteriorly, but extending beyond palatine posteriorly. 



Dentition. — From one skujl in my collection. Maxillary : 

 Postnodal, 4 to 6 ; scapModont. Palatine : 1 ; anododont, 

 isodont ; no edentulous space posteriorly. Pterygoid : 10 ; 

 anododont, scaphiodont ; posterior half edentulous. Mandi- 

 bular : 15 ; anododont, scaphiodont. 



There is one species, viz., ohscurua. 



PoBEECTicoiJJS OBSCURUS (Daudin). 



(Latin " obscurus " dark.) 



Russell's Seasnake. 



Tamil : " shootur sun," " kala shootur sun " (Russell). 



Synonymy. — Hydrophis obscurus, H. chloris, H. coronatus, 

 H. latifasciatus, Pelamis obscurus, P. chloris, Distira obscura. 



General Characters. — A snake of fair proportions, growing to 

 4 feet in length. Head small, elongate, not depressed. Snout 

 long, moderately declivous, subconical, turned dovm shghtly 

 terminally. Eye small. Commissure of mouth turned up 

 behind. Neck not contracted. Body cylindrical and slender 

 in the anterior two -fifths, the depth about one-third to one- 

 fiif th the depth at greatest girth ; much compressed and heavy 

 in the posterior three-fifths. 



Identification. — The costals 19 to 23 two heads-lengths 

 behind the head, taken with the imbricate scales in from 25 to 

 32 rows at the greatest girth and ventrals numbering 277 to 

 364, will suffice to distinguish it from other hydrophids. 



Colouration. — The young are very handsome, being bright 

 yellow, banded with from 34 to 60 broad black bands. These 



