288 OPHIDIA. 



HERPETON. 



Erpeton, Lacepede. 



Head depressed, of moderate length, distinct from neck ; snout termi- 

 nating in two flexible, cylindrical, scaly tentacles ; body and tail rather stout, 

 rounded. Cleft of the mouth of moderate width, turned upwards behind. 

 Eye small, with vertical pupil. Head shielded above, with the occipitals 

 well developed. Nostril on the upper side of the head, in the middle of a 

 large nasal, the outer portion of which is divided by a groove running out- 

 wards from the nostril. The nasals form a broad suture together ; two 

 small triangular anterior frontals ; lateral shields of the head very small ; 

 eye surrounded by a ring of small orbitals, the su])erciliary being well 

 developed ; upper labials small ; chin-shields small, narrow % oblique. Scales 

 strongly keeled, in thirty-seven series ; ventrals very narrow, each with two 

 keels ; anal bifid ; subcaudals not differing from scales. Maxdlary with the 

 last tooth grooved. 



Only one species is known. 



Herpeton tentaculatum. 



Erpeton tentacule, Lacep. Bull. Sri. Soc. Philom. 1800, ii. p. 169. 

 Erpeton tentaculatus, Lcitr. Hist. Rept. iv. p. 190. 



Homalopsis Lerpeton, Schleg. Abbild. p. 50. pi. 16 (from a discoloured specimen). 

 Herpeton tentaculatum, Giintk. Proc. Zool. Soc. 1860, p. 114. pi. 23 ; and Ann. if Mag. Nat, Hist. 

 1861, viii. p. 26G. 



The nasal shields form a broad suture behind the rostral, each being as large as one of the 

 posterior frontals ; anterior frontals much smaller than posterior. Vertical broad, five-sided ; 

 occipitals well developed, rounded behind. Small portions, however, are broken off from the 

 shields mentioned, and intercalated between the regular shields ; they vary much in number 

 in different individuals. 



The rostral appendages are as long as the snout, and covered with scales similar to those 

 in the loreal region ; the upper labials are very small, from thirteen to fifteen in number ; 

 eye surrounded by a ring of small shields. The temporal region is covered with keeled 

 scales similar to those on the neck. AU the scales are keeled, in thirty-seven rows. Ventrals 

 133-136, each being only twice as large as a scale. 



