no. 2078. REPTILES OF NORTHWESTERN NEVADA— RICHARDSON. 423 



dark blotches on the neck varying in intensity. From three to five 

 irregular pairs of dark blotches or lines, usually black, on the back. 

 Tail transversely banded with broad gray or reddish stripes with 

 darker posterior borders. The whole dorsal pattern in some specimens 

 is confused. Under surface white, immaculate, or irregularly spotted 

 with black or slate. 



Habits. — PJirynosoma platyrMnos was invariably found on the 

 desert among low bushes, under which it ran when pursued. It 

 seemed to rely upon this method of escape rather than that of hiding 

 in the burrows of small mammals, a habit of many desert lizards. 

 When hard pressed it crawled close to the stalk of a bush, around 

 which it dodged with considerable alacrity. When it ran any great 

 distance it often raised its tail above the level of the sand in a manner 

 suggestive of the more agile Callisaurus. 



Two individuals whose stomachs were opened had eaten a mass of 

 insects, chiefly ants and beetles, besides a number of larvae which 

 could not be identified. 



A female captured during the last week in May contained 13 large 

 eggs. Two others taken on June 2 held 9 and 13 eggs, respectively. 



PHRYNOSOMA DOUGLASSII HERNANDESI (Girard). 



Locality. — Five females of this species were collected at Deeth, 

 Elko County, Nevada, on July 5, furnishing a newrecord for the Lahon- 

 tan Basin. Yarrow ( 1882 b) lists as PJirynosoma douglassii douglassii 

 two specimens from Saint Thomas, Arizona. Saint Thomas is in 

 Lincoln County, Nevada, and the specimens, though now lost, prob- 

 ably represented this form. 



Status and variation. — All these specimens have large, reddish head 

 spines and occipitals projecting backward parallel with the temporals, 

 except in one specimen in which the occipitals are raised at a slight 

 angle. The parietal region of the head in the Nevada specimens 

 is but little lower than the frontal region, while many specimens from 

 Arizona and New Mexico show a decided depression of the former. 

 Associated with this peculiarity, is a well marked antero-posterior 

 curvature of the supraorbital ridge, which in most of the specimens 

 examined from Arizona and New Mexico is quite straight. However, 

 these characters are subject to considerable variation in all the speci- 

 mens with which the Nevada series was compared. The five speci- 

 mens have exposed tympani; the femoral pores range from 13 to 18, 

 average 15.8. 



The color in the preserved specimens is as follows : Head brown or 

 reddish brown. Two large black nuchal patches and at least two more 

 blotches on either side of the back each bounded posteriorly with 

 an interrupted white line. Under surface dull white variously 

 marked with slate. 



