133. HERPETON, . 25 
the snout; eye between four shields, viz. a supraocular, a preocular, 
a subocular. and a small postocular ; seven upper labials; five lower 
labials in contact with the anterior chin-shields ; posterior chin- 
shields extremely small. Scales in 35 to 43 rows. Ventrals 
153-165 ; anal divided; subcaudals 22-35. Pale grey or brownish 
above, with black cross-bands as broad as the interspaces between 
them or narrower; lower parts white. 
Total length 485 millim.; tail 50, 
Mouths of rivers and coasts of Pegu, Siam, and the Malay 
Peninsula. 
a-b. 3 (Se. 87; V. 160; C. 34) Pinang. Dr. Cantor. 
& yg. (Sc. 39; V. 155; C. 35). 
ce. 2 (Se. 48; V.160; C. 27). Pinang. F. Day, Esq. [P.]. 
d. g (Se. 41; V.160; C.31). Bangxok. Christiania Museum. 
e 
. 6 (Sc. 39; V. 165; C. 33). Pegu. W. Theobald, Esq. [C.}. 
St. & (Se. 39; V. 157; C. 33). P (Type of Bitia hydroides.) 
g. 2 (Se. 89; V.161; C. 24). —? (Type of Hipistes fasciatus.) 
h. Q (Se. 41; V. 161; C. 27). —P? 
133. HERPETON. 
Erpeton, Lacép. Bull. Sc. Soc. Philom. ii. 1800, p. 169, and Ann. 
Mus. ii. 1803, p. 280; Gray, Cat. Sn. p. 62 (1849) ; Dum, §& Bibr. 
Erp. Gén. vii. p. 983 (1854). 
_ Rhinopirus, Merr. Tent. Syst. Amph. p. 81 (1820). 
Herpeton, Wagl. Syst. Amph. p. 169 (1880) ; Giinth. Proc. Zool. Soc. 
1860, p. 115, and Ann. §& Mag. N. H. (8) viii. 1861, p. 266, and 
Rept. Brit. Ind. p. 288 (1864) ; Jan, Arch. Zool. Anat. Phys. iii. 
1865, p. 255. 
Homalopsis, part., Schleg. Phys. Serp. ii. p. 332 (1837). 
Maxillary teeth 12 or 13, followed, after a short interspace, by a 
pair of slightly enlarged grooved teeth ; mandibular teeth subequal. 
Head distinct from neck, with two long, scaly, rostral appendages ; 
eye small, with vertically elliptic pupil; head-shields large; nostril 
in a semidivided nasal, which is separated from its fellow by a series 
of small scales ; loreal region covered with small scales; no regular 
chin-shields. Body cylindrical; scales strongly keeled, in 37 rows ; 
ventrals very narrow, bicarinate. Tail moderate, covered with 
uniform keeled scales. 
Cochinchina and Siam. 
1. Herpeton tentaculatum. 
Erpeton tentaculatus, Lacép, Bull. Sc. Soc. Philom. ii. 1800, p. 169, 
and Ann. Mus, ii. 1803, p. 280, pl. 1.; Daud. Rept. vii. p. 246, 
pl. Ixxxyi. (1803); Gwér. Icon. R. A., Rept. pl. xx. fig. 3 (1844) ; 
Gray, Cat. p. 68 (1849); Dum. § Bibr. vii. p. 984 (1854). 
Rhinopirus erpeton, Merr. Tent. p. 82 (1820). 
Homalopsis herpeton, Schleg. Phys, Serp. ii. p. 359 (1837), and 
Abbild. p. 50, pl. xvi. (1839). 
Herpeton tentaculatum, Jan, Icon. Gén. 1, pl. i. (1860); Giinth. 
Proc. Zool, Soc. 1860, p. 114, pl. xxiii. ; Cornalia, Rev. § Mag. Zool. 
