9f). ARRHYTON. 251 



Snout shorter than in L. torquatus ; upper portion of rostral as 

 long as its distance from the frontal ; prajfrontal separated from the 

 eye by a small pra30cular. Scales in 17 rows. Veutrals 191 ; sub- 

 caudals 93. Uniform grey-brown above, yellowish white beneath 



Total length 34(i millim. ; tail 105. 



Isthmus of Tehuantepec. 



3. Leptocalamus sclateri. (Plate XII. fig. 1.) 

 Hostral smaller than in L. torquatus, nearly twice as broad as 

 deep, the portion visible from above measuring about one third its 

 distance from the frontal ; iuternasals shorter than the prefrontals, 

 which largely enter the eyes ; frontal large, kite-shaped, slightly 

 longer than broad, much longer than its distance from the end of 

 the snout, as long as the parietals ; supraocular very small ; loreal 

 longer than the nasals ; no praeocular ; two postoculars ; temporals 

 14-2 ; seven upper labials, third and fourth entering the eye; five 

 small equal chin-shields, the anterior a pair in contact with three 

 labials. Scales in 15 rows. Yentrals 144 ; anal divided ; sub- 

 caudals 98. Uniform dark brown above ; head yellow, with a black 

 blotch on the snout and another round each eye ; lower parts uni- 

 form yellowish. 



Total length 380 millim. ; tail 150. • 



S. America. 



a. ? (V. 144 ; C. 98). S. America. P. L. Sclater, Estj [P.]. 



96. ARRHYTON. 



Arrhyton, Gi'mth. Cat. Col. Sn. p. 244 (1858). 



Cryptodacus, Gundl. ^- Peters, Mon. Berl. Ac. 18G1, p. 1002 ; Bocourt 



Mus. Sc. Me.v., Rept. p. 500 (1883). 

 Colorhogia, Cojye, Proc. Ac. Philad. 1862, p. 81. 



Maxillary bone short, with 8 small teeth, foUowed, after a con- 

 siderable interspace, by a strongly enlarged fang; palatine and 

 pterygoid teeth few ; mandibular teeth small, equal. Head slightly 

 distinct from neck; eye rather small, with round pupil; nasal 

 entire or semidivided. Body cylindrical, moderately elongate ; scales 

 smooth, without apical pits, in 15 or 17 rows ; ventrals rounded, 

 iail moderate ; subcaudals in two rows. 



Cuba. 



&jnopsts of the Species. 



Nasal semidivided; praefrontals distinct, in 



contact with labials 1. Uvniatum, p. 252. 



Wasal entire; prefrontals and loreal distinct. 2. vktatwn,^. 2h2 

 Nasal entire; prefrontals coalesced; loreal 



'^'^ti'^^t 3_ redimitum, p. 252. 



