142 OPHIDIA. 
Body and tail encircled by black rings, which are shorter than the head, but wider 
than the interspaces; there are about forty of these rings on the trunk. Head 
irregularly spotted with brown. . 
The single specimen known is 174 inches long, the tail measuring 6 inches. 
3. Leptognathus argus. 
Leptognathus argus, Cope, Journ. Ac. N. Se. Phil. viii. p. 130 (1875). 
Hab. Costa Rica, Sipurio (Cope). 
4. Leptognathus pictiventris. 
Leptognathus pictiventris, Cope, Journ. Ac. N. Sc. Phil. viii. p. 180 (1875). 
Hab. Costa Rica. 
5. Leptognathus articulatus. 
Dipsas brevis, Cope, Proc. Ac. N. Sc. Phil. 1860, p. 266 (nec Dum. & Bibr.). 
Leptognathus articulata, Cope, Proc. Ac. N. Se. Phil. 1868, pp. 107, 135. 
Hab. Costa Rica; Panama, Veragua. 
6. Leptognathus viguierl. 
Leptognathus viguieri, Bocourt, Bull. Soc. Philom. viii. p. 136 (1884). 
Hab. Panama, Isthmus of Darien. 
I have not seen a specimen of this or of the preceding species; to judge from the 
descriptions, these snakes must be closely related to each other. 
7. Leptognathus brevis. 
Leptognathus brevis, Dum. & Bibr. Erpét. vil. p. 476. 
Hab. Mexico (Mus. Paris). 
8. Leptognathus brevifacies. 
Tropidodipsas brevifacies, Cope, Proc. Ac. N. Se. Phil. 1866, p. 127. 
Leptognathus brevifacies, Cope, ibid. 1868, p. 108. 
Dipsadomorus fasciatus, Bocourt, Bull. Soc. Philom. viii. p. 185 (1884). 
Leptognathus torquatus, Cope, Proc. Am. Phil. Soc. xxii. p. 172 (1885). 
Hab. Mexico, Yucatan (Smiths. Inst. and Mus. Paris). 
9, Leptognathus semicinctus. 
Leptognathus semicinctus, Bocourt, Bull. Soc. Philom. viii. p. 189 (1884). 
Hab. Mexico; Guatremaua, Alta Vera Paz (Bocourt). 
