120 RHINOCHEILUS. 



Genus RIIl]\OCHEIL,lJS5 Baird & Girard. 



Gen. Char, Head subelliptical, pointed on the snout, and sepa- 

 rated from the body by a contracted neck. Rostral plate large, but 

 not prominent above. Two pairs of frontal plates. Vertical hex- 

 agonal. Two nasals; nostrils intermediate. One loral. One an- 

 terior and two postorbitals. Superciliaries large. Eyes also large, 

 over the 4th and 5th upper labial. Mouth large. Scales smooth, in 

 23 rows. Postabdominal scutella entire. Subcaudal scutellae all un- 

 divided. 



RIlillocIaeillES liecontei, B. & G. — A dorsal series of quadrate 

 black blotches, ■with the intermediate spaces of the same size, and pale 

 red. Flanks variegated -with yellowish and black; beneath lighter, 

 unicolor. 



Head distinct from the body ; broad behind, nearly flat above. 

 Vertical plate hexagonal, elongated, largest anteriorly, the lateral 

 edges tapering, and constituting the longest sides of the figure. 

 Superciliaries quite large. Occipitals subangulai', proportionally 

 small. Prefrontals large compared to the postfrontals. Rostral 

 prominent forwards, rounded beneath, tapering upwards. Eyes large, 

 over the junction of the 4th and 5th upper labials, about opposite 

 the middle of the commissure. Postorbitals two, lower in notch be- 

 tween the 5th and 6th labials, although resting more on the latter. 

 Anteorbital large, resting on the 4th labial, the 4th and 5th 

 labials constituting equally the inferior part of the orbit. Loral 

 elongated, horizontal, trapezoidal, well developed. Nasals apparently 

 double, perhaps a single one very much excavated. Two temporal 

 shields between the occipitals and labials. Labials 8 above, 7th 

 largest; 8 below, 5th largest. Dorsal rows of scales 23, all per- 

 fectly smooth ; scales rhomboidal, nearly equal, but rather narrow 

 above. Abdominal scutellse 206 ; posterior one entire. Subcaudal 

 scutellse 40, all entire. 



