26 



CALIFORNIA ACADEMY OF SCIENCES 



[Proc. 4th Sek. 



222 to 258, males having from 222 to 237, females from 227 

 to 258; the average in six males is 227, in nine females, 237. 

 The urosteges vary from 52 to 68, males having from 57 to 68, 

 females from 52 to 60; the average in six males is 63.5, in nine 

 females, 57. 



The dark blotches between head and anus in 16 specimens 

 vary from 37 to 55, the average being 46. On the tail they 

 vary from 10 to 14, and average 12.5. The counts of these 

 blotches are given in full below. 



Distribution. — I have examined specimens of the Arizona 

 Gopher-Snake taken at Yuma, Yuma County, the Colorado 

 River above Bill Williams River, Mohave County, Cave Creek, 

 Maricopa County, Fort Lowell and the Santa Cruz River 

 near Tucson, Pima County, and the Huachuca Mountains, 

 Cochise County, Arizona. Specimens of Pituophis from Ari- 

 zona have been recorded as collected at Oak Orchard, Camp 

 Grant, Wilton Springs, Tucson, Gila River, White River Can- 

 yon, Fort Whipple, Grand Canyon, and at Las Gijas in Pima 

 County. 



Remarks. — The specimens from Mohave and Yuma counties, 

 and a specimen from Silsbee, Imperial County, California (re- 

 ferred to P. c. deserticola) show more or less intergradation 

 between the Arizona and the Desert Gopher-Snakes. These 

 specimens have very many gastrosteges, while those from ex- 

 treme southeastern Arizona have fewer. Indeed, some of the 

 latter have so few as to indicate intergradation with the gopher- 

 snakes of New Mexico which Ruthven has referred to P. c. 

 sayi, but which may possibly require recognition as a distinct 

 subspecies, P. sayi dlinis (Hallowell). 



