460 AMBLYCEPHALID&, 
sixth, and seventh entering the eye ; symphysial in contact with a 
small azygous chin-shield followed by three pairs of chin-shields, 
the anterior longer than broad. Scales in 15 rows, vertebrals not 
enlarged. Ventrals 185-195; anal entire; subcaudals 98-126. 
Body with blackish-brown or reddish dark-edged annuli separated by 
narrower interspaces which may be whitish, black-spotted, or dark 
brown above and whitish powdered with brown beneath; head 
dark brown above, 
Total length 620 millim.; tail 205. 
Central America. 
a. 2 (V. 186; C. 100). Mexico. (Type) 
b. go (V.188; C.114). Hacienda Rosa deJericho, Dr. E. Rothschuh 
Nicaragua, 3250 ft. [C.]. 
21. Leptognathus bicolor. 
ar bicolor, Giinth. Biol. C.-Am., Rept. p. 178, pl. lvi. fig. C 
Body very slender, very strongly compressed. Eyelarge. Rostral 
broader than deep, scarcely visible from above ; internasals two thirds 
the length of the prefrontals; frontal as long as broad, as long as 
its distance from the end of the snout, shorter than the parietals ; 
nasal entire; loreal as long as deep, bordering the eye ; a preocular 
above the loreal; three postoculars ; temporals 24+3,; eleven upper 
labials, fourth to seventh entering the eye ; first lower labial in con- 
tact with and partially fused with its fellow behind the symphysial ; 
three large azygous chin-shields, followed by a pair. Scales in 15 
rows, vertebrals not enlarged. Ventrals 195; anal entire ; subcaudals 
129. Annulate black and white, the white annuli much narrower 
than the black ones, the first across the occiput ; the snout, chin, and 
upper head-shields black. 
Total length 565 millim.; tail 190. 
Nicaragua. 
a. & (V. 195; C.129). Chontalez, Nicaragua. R. A. Rix, Esq. [0.]; 
16; 2140, Oa Mame 
Esq. [P.}. (Type.) 
4, DIPSAS. 
Dipsas, Laur. Syn. Rept. p. 89 (1768). 
owls sh ey Oo ye Mus. xvi. 1810, p. 391. 
Dipsas, part., Bote, Isis, 1827, p. 548; Wagl. Syst. Amph. p. 180 
(1830); Schleg. Phys. Serp. li. p. 257 (1837); Cope, Proc. Ac. 
Philad, 1860, i 265. 
—— m. & Bibr. Mém. Ac. Se. xxiii. 1853, p. 467, and 
rp. Gén, vii. p. 468 (1854). 
Leptognathus, pert Giinth, Cat. Col, Sn. p. 177 (1858) ; Cope, Proc. 
Ac, Philad, 1868, p. 107. 
Dipsadomorus, part., Jan, Elenco sist. Ofid. p. 99 (1863). 
Maxillary bone with the toothed border turned inwards, forming 
