346 University of California Puhlicafions in Zoologij. [Vol. 7 



in various stages of development, and the resemblance of the 

 oldest to Scaphiopns, together with the probability that the 

 spadefoot was breedini>' there and at that time, makes a strong 

 circumstantial case for their lieing referable to it. 



THE REPTILES 



Crotaphytus collaris baileyi Stejneger 

 Bailey Lizard 



Distribution. — The eleven specimens of this form were all 

 taken near Big Creek Ranch, at altitudes ranging from 4800 feet 

 to 5400 feet. 



The species is reported from a number of localities in Nevada 

 and the northern Great Basin (see Van Denburgh, 1897, p. 56). 

 The present furnishes the first definite record for northern 

 Nevada. The localized range of the species in this locality indi- 

 cates that its distribution over the Great Basin is discontinuous. 



Habits. — We looked in vain for this lizard on the open desert 

 and on certain of the lower slopes of the mountains. All but one 

 were secured on top of a steep-sided, rocky ridge (altitude 5000 

 feet) near Big Creek Ranch. The exception was collected in Big 

 Creek Canon just below the Dugout Camp (4800 feet) and at 

 the base of the steep-sided ridge just mentioned. 



One was apparently resting in a groove on one of the stones. 

 We saw none on very large boulders. Crotaphytus c. baileyi does 

 not seem to be as adept at clinging to rocks in any position as is 

 Sceloporus biseriatus. The movements of Crotaphytus c. baileyi 

 resemble those of C. ivisUzenii. 



Some of the individuals taken were probably paired; at any 

 rate, their being secured close together might so indicate. 



The Bailey lizard is a nimble animal, jumping short distances 

 from i-ock to rock. Frequently individuals allowed of very close 

 approach, remaining perfectly quiet (see Ruthven, 1907. p. 513), 

 but at other times they retreated with great rapidity. 



The example taken in Big Creek Canon was just shedding its 

 epidermis, fragments of the old skin being still adherent. 

 Crotaphytus wislizenii Baird and Girard 

 Leo[)artl Lizard 



DIslrihulion. — Recorded from the following localities: Amos 



