50 SYNOPSES AND DESCRIPTIONS. 



Spilotes MELANURUS. 

 Dumh-U & Bibron, 1854, Erp. Gen. VII, 224. 



Specimens belonging to this species differ from those of S. variabilis in 

 that the posterior two thirds of the body are entirely black. Temporals 

 1+14-2. Labials eight. Keels on the scales obsolete, faintly indicated 

 near the middle of the body. Rows of scales 16, Ventrals 226. Anal 

 entire, Subcaudals 123 pairs. Total length 58^ inches ; tail lo| inches. 



'Spilotes auriisundus. 



Cope, 1861, /V. Ac. N. Sc, Phil., 300. 



Labials eight, ultimate as high or higher than the penultimate, fifth 

 large, approaching or reaching the postocular. Scales in 18 or 19 rows, 

 weakly keeled, first four or five smooth. 



Crown of head yellow, crossed by four more or less irregular cross-bands 

 of black. Posterior third of body crossed by numerous narrow, chevron- 

 formed cross-bands of yellow ; the tail annulate with the same, Mirador, 

 Vera Cruz. 



Spilotes roEciLONOTrs. 



G-unther, 1858, Cat. Col. Snakes in Brit. Mas., 100. 



Elongate, compressed; head distinct from the neck, rounded in front; 

 tail slender. Rostral broader than high, just reaching the top of the head. 

 Internasals short, broader behind ; prefrontals much larger. Frontal broad 

 in front, obtuse-angled behind. Supraciliaries broad behind. Parietals 

 short. One preocular, not reaching the frontal. Postocnlars two. Loreal 

 present. Nasal divided. Labials nine, fourth, fifth, and sixth in orbit. 

 Scales elongate, much imbricate, in 21 — 23 rows, dorsal keeled, the three 

 vertebral most strongly. Ventrals raised on the sides. Anal entire. 

 Subcaudals in two rows. 



Uniform brown above, with the exception of some scab's in the medial 

 row, which are yellow, with black tip. Head yellow ami brown varie- 

 gated. Belly yellow anteriorly. Ventrals black-edged about the middle 

 of the body, becoming entirely black posteriorly. Total length 63 inches; 

 tail 18 inches. Honduras, Mexico, 



