CROCODILIANS, LIZARDS, AND SNAKES. 



1191 



CROTALUS LEPIDUS Kennicott. 



Crolalus lepidas Ivk.vnicott, Proc. Acad. Nafc. Sci. Phila., 1861, p. 20(5.— Coi-k, 



I'roc. Acad. Nat. Sci. Phila., 1883, p. 13. 

 Jploaspis lephla CoPio, Report U. S. Geog. Surv. W. of 100th Mtji-., 1875, p. 53.5. — 



CoPK, Check-list N. Auier. Batr. Rept., 1875, p. 33. 



Fig. 344. 

 Crota!,us lepidds Kennicott. 

 = 1. 

 Rio Grande, Texas. 



Head ovoid, tapering to the nose, wliicli is narrow, pointed, and 

 depressed. Nostril small, circular, and placed near the point of the nose 

 in about the middle of a nasal plate, which is nsually only divided from 

 the nostril downward. Two elongated internasals in contact, extending 

 behind the nostrils. Superciliaries and other large plates smooth. 

 Rostral subtriaugular, broader than high, the apex turned back slightly 

 upon the crown. Upper preorbital small and separated from the post- 

 nasal by the width of two larger loreal jilates. Labials rather large, 

 twelve above, ten to twelve below. Color of head yellowish ash. 



The head is nuich depressed, the general outline ovoid, tai)ering 

 regularly from about opposite the angle of the mouth to the nose. The 

 crown is remarkably smooth and the occipital scales are very faintly 

 carinated. There are two large internasals elongated laterally and 

 iwsteriorly, with their inner ends in contact. They are convex on their 

 external and concave on their internal edges, and extend for nearly 

 half their length back of the nostril. Behind and litting into the 

 emarginatiou formed by these are two subciuadrangular and sujaller 

 plates in contact. Immediately behind these is another similar pair. 

 On each side of these last two pairs, at the edge of the crown, between 

 the superciliaries and anterior frontals, is a larger plate. The super- 

 ciliaries are rather small, and, like the other larger plates, quite smooth; 

 the space between the superciliaries is quite narrow and filled with 

 three rows of irregular large scales; the i)osterior part of the crown is 

 also covered with rather large and smooth scales. The lower preorbital 



