462 AMBLTCEPHALID^. 



PLeptognathus (Dipsadomorus) cisticeps, Boettg. Zeitsehr. ges. 

 Naturw. Iviii. 1885, p. 237. 



Rostral as deep as broad or a little deeper than broad, scarcely 

 visible from above ; internasals not more than balf the length of the 

 praefrontals ; frontal as long as broad or slightly longer than broad, 

 as long as or shorter than its distance from the end of the snout, 

 much shorter than the parietals ; nasal entire ; loreal not or but 

 scarcely longer than deep, entering the eye ; a prseocular above the 

 loreal; two postoculars ; temporals 1 or 2+2 or 3; eight to ten 

 upper labials, fourth and fifth, fifth and sixth, or fourth, fifth, and 

 sixth entering the eye ; two lower labials in contact with each other 

 behind the symphysial ; two to four pairs of chin-shields. Scales in 

 13 rows, vertebral row strongly enlarged. Ventrals 171-200 ; anal 

 entire; subcaudals 91-116. Yellowish, greyish, or reddish brown 

 above, with more or less distinct dark cross-bands or triangular spots 

 on the sides ; a series of whitish spots, corresponding to the light 

 interspaces along each side, partly upon the ventral shields ; head 

 with dark, light-edged spots ; lower parts brownish, speckled with 

 white. 



Total length 680 millim. ; tail 250. 



Tropical South America. 



a. c? (V. 198; 0. 116). Demerara. Zoological Society. 



b. Hgr. (V. 185 ; C. 105"). Bahia. Dr. OTWucherer fO.]. 



c. Hgr. (V. 191 ; 0. 106). Ecuador. Mr. C. Buckley [Cj 

 £?-e. c? (V. 171 ; C. 92) & Moyobamba, N.E. Mr. A. H. Roff [O.j. 



$ (V. 177 ; 0. 91). Peru. 



/. $ (V. 191 ; 0. 99). Charocampa, Bolivia. 



g. S (V. 194 ; 0. 101). ? Dr. Gunther [P.]. 



h. SkuU of e. 



6. PSEUDOPAEEAS. 



Leptognathus, part., Jan, Elenco sist. Ofid. p. 100 (1863). 



Head distinct from neck ; eye moderate, with vertical pupil. Body 

 cylindrical ; scales smooth, in 15 rows, vertebral row slightly enlarged ; 

 ventrals rounded; subcaudals intsro rows. 



South America. 



1. Pseudopareas vagus. 



LeptogDathus vagus, Jan, I. c, and Icon. 06n. 37, pi. vi. fig. 2 (1870) ; 



Cope, Proc. Ac. Philad. 1868, p. 136. 

 Pareas vagus, Boettg. Ber. Offenh. Ver, Nat. 1888, p. 145. 



Rostral nearly as deep as broad ; internasals shorter than the prse- 

 frontals ; frontal a little longer than broad, as long as its distance 

 from the end of the snout, much shorter than the parietals ; loreal 

 twice as long as deep, entering the eye ; a small prseocular between 

 the loreal and the supraocular ; two postoculars ; temporals 1-|- 2 ; 

 eight upper labials, fourth and fifth entering the eye ; first lower 

 labial in contact with its fellow behind the symphysial ; three pairs 



