186 MAJOR F. WALL, I.M.S., C.M.Z.S. 



Platurus colubrinus (Schneider.) 



Mydrus colubrinus, Schneid., Hist. Amph., 1799, i, p. 238. 



? Hydrophis colubrinus, Schlegel, Phys. Serp. ii, 1837, p. 514, pi. xviii, figs. 



21 and 22. 

 Platurus colubrinus, Boulgr. in Blanford, Fauna Ind. Rept. and Batrach., 1890, 



p. 395 and Cat. iii, 1896, p. 308. 

 ,, ,, Sclater, List Snakes Ind. Mus., 1891, p. 62. 



, fJ Wall in Proc. Zool. Soc. Lond., 1903, pp. 96 and 101. 



„ fasciatus, Jan, Icon. Gen., 1872, livr. 40, pi. i, fig. 1. 

 ,; scutatus, Giinther , Rept. Brit. Ind., 1864, p. 356. 



A B C 



Fig. 3. — Platurus colubrinus (nat. size). 



I have examined upwards of twenty of this species. 



Description. — Rostral, — touches six shields; the rostro-labial sutures much the 

 largest. Internasals,-a pair. Prefrontal s, — three subequal shields in one trans- 

 verse row; the outer touching no supralabial. Frontal, — entire; touches seven 

 shields; the fronto-parietal sutures largest. Supraoculars, — half to about two- 

 thirds as broad, and as long as the frontal. Parietal s, — entire. Nasals, — lateral ; 

 in contact with the first three supralabials usually (sometimes only the first two). 

 Praeoculars, — one. Postoculars, — two. Temporals, -one (sometimes two). 

 Supralabials, — seven ; the third and fourth touching the eye. Infralabials, — 

 the fourth is the largest of the series, and in contact with three or four scales 

 behind. Marginals, -a complete row after the second infralabial. Sublinguals, — 

 two well developed pairs, the fellows of each in contact. Cost a Is, anteriorly 21 to 25, 

 midbody 21 to 25, posteriorly usually 21 (rarely 23) ; imbricate ; smooth. Ventrals, 

 — 195 to 240 ; three or more times as broad as the last costal row ; the last one or two 

 very frequently divided. Anal, — divided. Colour, — like the last, but in old speci- 

 mens the bands are often effaced ventrally, and converted into dorsal bars. 



Habitat. — From the Bay of Bengal through the Malayan Region, China, Philip- 

 pines to Australia and New Zealand. 



EMYDOCEPHALUS . 



Key to the species of Emydocephalus. 



(A) Prefrontals 4 ; vertebrals much enlarged ; costals smooth; a ventral 



keel posteriorly . . . . . . . . . . ijimce. 



(B) Prefrontals 2 ; vertebrals not enlarged ; costals tuberculate ; no ven- 



tral keel . . . . . . . , . . . . annulatus. 



