136 



smooth scales, without pits, in 15 or 17 rows; ventrals rounded. 

 Tail moderate; subcaudals in two rows. 

 Distribution. Borneo. 



Key to the I ndo-A ustralian species. 



A. Scales in 17 rows; two praefrontals I. H. periops p. 136. 



B. Scales in 15 rows; a single praefrontal 2. H. praefrontalis p. 137. 



i. Hydrablabes periops (Gunther). 



Ablabes periops, Gunther, Proc. Zool. Soc. 1872, p. 595, fig. 3. 

 Hydrablabes periops, Boulenger, Cat. Sn. I 1893, p. 296. 



Snout short and broad; rostral just visible from above; 

 internasals not half as large as the praefrontals, usually in 

 contact with the loreal; frontal more than twice as broad as 



Fi g- 55- Hydrablabes periops (Gthr.). Nat. size. Side view of head. 



the supraocular, as long as its distance from the tip of the 

 snout, much shorter than the parietals; loreal nrore long than 

 deep; two prae-, two post- and two or three suboculars; tem- 

 porals 1 + 2; eight or nine upper labials, all separated from 

 the eye; three pair of chin-shields, second largest and sepa- 

 rating the third. Scales in 17 rows; ventrals 190 209, the 

 last divided; anal divided; subcaudals 62 74. 



