CROTAPHYTUS 115 



Description. — Head large, depressed, and very distinct 

 from the neck on account of swollen temples. Snout larger 

 than in C. c. bailey i. Its plates all small but largest and 

 somewhat convex on snout and frontal region. Two longi- 

 tudinal rows of shields separating supraocular regions. 

 Nostrils large and opening laterally, each in a round plate 

 nearer to end of snout than to orbit. Superciliaries small 

 but imbricate. Supralabials rather prominent and of nearly 

 equal size. A large subocular plate, sometimes divided. 

 Ear-opening large, oblique, with very slight anterior dcn- 

 ticulation. Supraoculars, temporals and gulars subgranular. 

 I-ower labials a little larger than upper, bordered below by 

 several series of plates larger than gulars. Symphyseal 

 plate large, followed by a pair of large shields. One or 

 two gular folds, continued on sides of neck. Back and sides 

 covered with small granules which pass gradually into 

 larger smooth flat scales on belly. Sides irregularly plicate. 

 Tail tapering, nearly twice as long as head and body, and 

 furnished with whorls of small, smooth plates which become 

 keeled distally. Femoral pores varying in number from 1 7 

 to 22 in each series. Males with enlarged postanal plates. 



The general color is bluish, grayish, or yellowish brown, 

 variously marbled, blotched, reticulated and cross-lined with 

 pale gray or white. A whitish or grayish band crosses the 

 shoulders. In front of this is an incomplete black collar 

 or blotch in front of the shoulder. The head is spotted and 

 reticulated with dark brown laterally and inferiorly. The 

 throat and sides of belly are white more or less suffused 

 with grayish blue; the belly sometimes with large brown 

 or black lateral blotches and spots, the largest often just in 

 front of the thigh. The upper surfaces of the limbs and 

 tail are grayish or yellowish, spotted or reticulated with 

 brown. 



