no. 2078. REPTILES OF NORTHWESTERN NEVADA— RICHARDSON. 407 



with these, lacked the continuous black collar and black patches on 

 the belly. 



The females are lighter ventrally than the males. In preserved 

 specimens, the markings on the throat and sides of head are very 

 faint, the belly is white suffused with blue-gray and the anterior 

 black collar is wanting below. 



Habits. — This lizard was found only on hillsides among deposits of 

 tufa and outcroppings of volcanic rock at an elevation of 4,500 feet. 



CROTAPHYTUS WISLIZENII Baird and Girard. 



Locality. — The collection contains 13 specimens from the Pyramid 

 Lake Indian agency, 3 from The Willows, Pryamid Lake, 1 from 

 Derby, 4 from Carson City, Nevada, and 2 from Doyle, Lassen County, 

 Calif ornia. Other points in the basin where it is known to occur are 

 Truckee River and Wadsworth, Washoe County; Amos, Quinn River 

 Crossing, Pine Forest Mountains, and Thousand Creek Flat, Humboldt 

 County, Nevada. 



Status and variation. — I can see no difference between this series 

 and specimens of Orotaphytus wislizenii from southern Idaho and San 

 Diego County, Cal. The width of the head, in the material examined, 

 seldom exceeds the distance from the nostril to the ear opening, and 

 the distance from the nostril to the inner orbital angle is nearly 

 always as great or greater than the vertical diameter of the ear 

 opening. These features will readily distinguish the specimens in 

 question from the nearly related CrotapTiytus situs Stejneger. The 

 measurements of 11 specimens are appended: 



Five 

 females. 



Greatest width of head: 



Minimum 



Average 



Maximum 



Nostril to ear: 



Minimum 



Average 



Maximum 



Nostril to inner orbital angle 



Minimum 



Average 



Maximum 



Vertical diameter of ear: 



Minimum 



Average 



Maximum 



Length, snout to anus: 



Minimum 



Average 



Maximum 



Length of tail: 



Minimum 



Average 



Maximum 



Femoral pores: 



Minimum 



Average 



Maximum 



16 



18.9 



22 



16 



18.6 



22.5 



4.5 

 5.6 



7 



4 



4.9 



5.5 



77 



93.6 

 115 



153 

 183.5 



217 



i Indicating number of individuals from which measurements were taken. 



