18 SYNOPSES AND DESCRIPTIONS. 



SlBON TORQUATUM. 



Leptodeira tokquata Gi'intlicr, 1860, Ann. & Mag. Nat. Hist., ph X, 169. 



Posterior maxillary tootli larger,* separated by an interspace. Scales in 

 21 rows. Ventrals 174. Anal bifid. Subcaudals 44 — 56. Total length 

 16 in. 51.; tail 3 inches. Total length 17 in. 51.; tail 2 in. 31. 



Brownish-grey, with a vertebral series of brown spots, some of which 

 are confluent into a zigzag band; neck with a white collar, behind which 

 there is a large brownish-black blotch. Hab. Nicaragua; Island of Laguna. 

 (Prom Giinther.) 



SlBON DISCOLOR. 



Leptodeira discolor Gimther, 1860, Pr. Zool. Soc. Load., 317. 



Posterior maxillary tooth larger, in a continuous series with the other 

 teeth, not grooved. Scales in 19 rows, smooth, rhombic, those of the sides 

 similar to those of the back. Ventrals 179 — 182. Anal bifid. Subcaudals 

 87—88. Total length 21 in. 1 1. ; tail 6 in. 



Dirty white, with numerous black cross-bands extending on to the ven- 

 tral plates ; belly uniform whitish. Fifty-one to fifty-four black bands cross 

 the trunk and extend to the edge of the belly ; they are broader than the 

 interspaces between, and become interrupted and spot-like on the tail. 

 Upper part of head brown, with a whitish collar behind the occipitals. 

 Separated from S. annulatum by the teeth. Hab. Oaxaca, Mex. (From 

 GKinther.) 



SCYTALINAE. 



Moderate, cylindrical to subcylindrical ; head distinct from the neck, 

 broad behind, croAvn flat; tail medium, tapering. Eye medium, pupil 

 oblong or elliptical. Crown-shields nine. Nasal generally divided. A 

 loreal. Preoculars one to two. Postoculars two. Posterior maxillary 

 teeth longer, grooved. Scales smooth, in 17 to 19 rows, occasionally the 

 vertebral series larger. Anal entire. Subcaudals simple or bifid. 



OXTRHOPUS. 



Wagler, 1830. 



Elongate and subcylindrical to slender and slightly compressed; head 

 moderate, a little larger than the neck, depressed, muzzle rather broad, 

 crown flat; tail short to moderate. Eye medium, pupil elliptical, erect. 



