404 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



vol. 48. 



and in Nevada at Reno, Derby, Wadsworth, vicinity of Pyramid 

 Lake Indian Agency, Washoe County; Carson City, Ormsby County; 

 Winnemucca, Humboldt County; Palisade, Eureka County; and 

 Deeth, Elko County. There are also included notes on certain 

 specimens in the Stanford University collection not heretofore pub- 

 lished, and for completeness all available published records have 

 been added. All measurements are given in millimeters. 



The greater part of this work was done in the zoological laboratory 

 of Stanford University, and I am indebted to Prof. J. O. Snyder, of 

 that institution, for many helpful suggestions. I am also under 

 obligations to Dr. L. Stejneger, Dr. John Van Denburgh, Dr. J. 

 Grinnell, and Prof. M. Herrick Spaulding, for the loan of specimens. 



GEOGRAPHICAL VARIATION IN CERTAIN WEST AMERICAN REPTILES. 



During the course of work upon this collection, a number of tangi- 

 ble differences between both the northern and southern and mountain 

 and plain forms of certain species have been found. In the case of 

 Cattisaurus ventralis and Uta stanshuriana, large series of specimens 

 have been available and a decision has been reached regarding their 

 status; specimens of other forms have not been so numerous and 

 I have chosen merely to indicate the differences in the material 

 examined. The following table shows the divergence in the species 

 of both series : 



Species showing differences coir elated with latitude. 



SOUTHERN FORM/ 



Callisaurus ventralis. 



(Southeastern California and southern 



Arizona. ) 

 Length greater (ratio body to tail 0.728). 

 Femoral pores more (average 16.6). 

 Color lighter. 



Uta stanshuriana elegans. 



(Desert of southeastern California, Ari- 

 zona, New Mexico, and Mexico.) 



'Tail length averages — male, 

 98.3 mm., female, 76.2 mm. 

 Size larger< Ratio hind leg to length from 

 snout to anus, averages — 

 . male 0.741, female, 0.699. 

 Femoral pores more (average 14+). 

 Dorsal scales fewer, larger and keeled 

 (average, 86.5). 



Sceloporus magister. 



(Fort Lowell and Tempe, Arizona.) 



Snout to anus, average, male, 



113.2 mm. 

 Tail length, average, male, 

 150.2 mm. 

 Femoral pores more (average 13+). 



Size larger- 



NORTHERN FORM. 



C. ventralis myurus. 



(Pyramid Lake, Nevada.) 



Length less (ratio 0.807). 

 Femoral pores less (average 14.2). 

 Color darker. 



Uta stanshuriana. 



(Northern Nevada, Oregon, Idaho, and 

 Utah.) 



(Tail length averages — male, 



174+ mm.; female, 67+ 

 mm. 

 Ratios — male, 0.714; female, 

 0.649. 

 Femoral pores less (average 13+). 

 Dorsal scales more, smaller and smooth 

 (average 103.4). 



Sceloporus magister. 



(Pyramid Lake, Nevada.) 



Snout to anus, average, male 



94 mm. 

 Tail length, average, male, 

 124.4 mm. 

 Femoral pores less (average 11+). 



Size smaller. 



