184 



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



PLATURUS. 



Key to the species of Platurus. 



(A Rostral touches five shields 

 (B) Rostral touches six shields 



(a) Frontal touches six shields 



(/;) Frontal touches seven shields 



schistorhynchus. 



laticaudatus. 

 cohtbrinus. 



Platurus schistorhynchus (Giinther). 



Platurus schistorhynchus, Giinther in Proc. Zool. Soc, 1874, p. 297; pi. xlv, 

 ,j ,, fig. A. Boulgr. in Blanford, Fauna Brit. Ind. Refit. 



1890, p. 375, and Cat. iii, 1896, p. 309. 



Fig. 1. — Platurus schistorhynchus (nat. size). 



I have examined over 40 examples. 



Description. Rostral, — touches five shields; the rostro-labial and rostro- 

 internasal sutures subequal, largest. Inter nasals, — one anterior succeeded by one 

 rather irregular row which might be considered either posterior internasals, or anterior 

 prefrontals. Prefrontals, — three in one transverse series, the outer not touching 

 any supralabial Frontal, — touches seven shields; the fronto-parietal and fronto- 

 supraocular sutures subequal and largest. Supraoculars, — -entire; about half as 

 broad and three quarters as long as the frontal. Parietals, — entire; as broad or 

 broader than long, shorter than the frontal. Nasal s, — lateral ; in contact with the first 

 three supralabials. Prseoculars, — one. Postoculars, — two. Temporals, — 

 two (rarely three) small. Supralabials , — seven ; the third and fourth touching the 

 eye. Infralabial s,— the fourth is the largest of the series, and in contact with three 

 scalesbehind. Marginals, — usually after the fourth infralabial. Sublinguals, — 

 anterior well-developed ; the posterior if they can be recognised as such, small, and 

 quite separated. Costals, — anteriorly 21 to 23, midbody 21 to 23 (usually 23), 

 posteriorly 19 to 21 ; smooth; imbricate. Ventrals 178 to 200; three or more times 

 as broad as the last costal row, the last one or two frequently divided ; the posterior 

 obtusely keeled in the median line. Anal, — divided. Colour, — broadly banded, 

 dark brown and yellowish or greyish ; the bands well defined, and the brown rather 

 broader. 



Habitat. — Loo Choo Islands, Moluccas, Savage Island, Society Islands, Samoa. 



