University of Michigan 



PLATE III. 



Figure i. One of the mountain valleys continuous with the main 

 valley of James Creek, showing the stony slopes, restricted outcrops 

 (background), and small groves characteristic of such valleys. The 

 stream is spring fed but disappears during the summer months. The 

 dominant plant on ithe ridges is the sagebrush. The reptiles and amphi- 

 bians found at the bottom were Hyla regilla, Bufo horeas and Scelop- 

 orus biseriatus (where rocks were present), Bascanion taeniatum, Bas- 

 canion constrictor vetustum and Pituophis catenifer descrticola. On 

 the stony slopes were found the last two species with Bumeces skil- 

 tonianus, Crotalus lucifer, and, in the few places where the soil was 

 very fine, Sceloporns graciosus. 



Figure 2. A rock outcrop in the Pinyon Range. These outcrops are 

 small, except where the permanent streams cut through the mountains, 

 and the}' are usually broken up into large blocks. Sceloporus biseriatus 

 is to be found on nearly every outcrop, and Hyla regilla, Crotaphytus 

 collaris baileyi, Uta stansbiiriana ncvadensis, Crotalus lucifer, Pituophis 

 catenifer deserticola, Bascanion taeniatuin and Bascanion constrictor 

 vetustum were also found in such places. 



