— ee Ue. — = 
—— ee 
Wo 
18. IscHNOGNATHUS. 285 
Rostral as deep as broad; internasals subcrescentic, forming 
together a triangle; two prefrontals; frontal as broad as long; 
one prie- and one postocular, and three suboculars separating the 
eye from the labials ; twelve upper labials, third to tenth separated 
from the edge of the mouth by a row of small trigonal scales. Scales 
in 17 rows, striated and strongly keeled. Ventrals 170; anal divided; 
subcaudals 95. Olive above, the scales with a whitish edge; lower 
parts and outer row of scales yellow. 
Kaju Tanam, Sumatra. 
4, Opisthotropis typica. 
Heli ides typicus, Mocquard, Le Natur. 1890, p. 154, and Nouv. 
Arch. Mus. (3) ii. 1890, p. 141, pl. ix. 
Snout short and broad, much depressed. Rostral twice as broad 
as deep; nasals semidivided, in contact behind the rostral ; inter- 
nasals small, triangular; a pair of prefrontals; frontal large, 
pentagonal, as long as broad; supraocular very small; loreal 
elongate, partly or completely divided; two pre- and two post- 
oculars; three suboculars separating the eye from the labials; 
temporals 1+1+2; eleven upper labials, seventh and eighth 
below the eye, the six anterior twice as deep as long, the four last 
divided as in the preceding species. Scales in 19 rows, striated 
and keeled. Ventrals 176; anal divided; subcaudals 82. Uniform 
olive-brown above, dirty yellow below. 
Total length 390 millim.; tail 95. 
Mt, Kina Baloo, North Borneo. 
18. ISCHNOGNATHUS. 
Ischnognathus, Dum. § Bibr. Mém. Ac. Se. xxiii. 1853, p. 468, and 
Erp. Gén. vii. p. 506 (1854) ; Giinth. Cat. Col. Sn. p. 80 (1858) ; 
Jan, Arch. Zook. Anat. Phys. iii. 1865, p. 238. 
Storeria, Baird § Gir. Cat. N. Am. Rept. p. 135 (1853). 
Microps (non Megerle), Hallow. Proc. Ac. Philad. 1856, p. 240. 
Tropi oclonion, Cope, Proc. Ac. Philad. 1860, p. 76, and Proc. U.S, 
Nat, Mus. xiv. 1892, p. 666. 
Cora, Jan, I. ¢. 
Adelophis (Duges), Cope, Proc. Am. Philos. Soc. xviii, 1879, p. 265. 
Clonophis, Cope, Proc. U.S. Nat. Mus. xi. 1889, p. 391. 
} Maxillary teeth 14 to 18, equal; mandibular teeth equal. Head 
: slightly distinct from neck; eye rather small, with round pupil; 
loreal shield present or absent. Body moderately elongate, cylin- 
drical ; scales keeled, with or without apical pits, in 15 to 19 rows; 
) ventrals rounded. Tail moderate; subcaudals in two rows. Hypa- 
| pophyses developed throughout the vertebral column, 
| orth and Central America. 
ig. 3. 
Sagi typica, Bouleng. Ann. § ge N. H, (6) vii. 1891, 
pom ; 
——— 
d 
f 
