736 13. COLUBRIDA 
6%; and 35 in one, or 6%; the average is 32.1 rows. The 
gastrosteges vary in number from 221 to 258, males having 
from 221 to 237, females from 227 to 258; the average in 
six males is 227, in nine females, 237. The urosteges vary 
from 50 to 68, males having from 57 to 68, females from 
50 to 60; the average in six males is 63.5, in nine females, 
Des 
The dark blotches between head and anus in 16 speci- 
mens vary from 37 to 55, the average being 46. On the 
tail they vary from 10 to 14, and average 12.5. 
Distribution.—\ 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 vicinity of Here- 
ford and Ramsey, Carr and Miller canyons in the Huachuca 
Mountains, Cochise County, Arizona. Specimens of Pituo- 
phis from Arizona have been recorded or collected at Oak 
Orchard, Camp Grant, Wilton Springs, Tucson, Gila River, 
White River Canyon, Prescott, Walnut, Fort Whipple, Fort 
Verde, Grand Canyon, Colorado Chiquito, Canyon Diablo, 
Camp J. A. Packer, Fort Mohave, and at Las Gijas, Pima 
County. 
Remarks——The specimens from Mohave and Yuma 
counties, and a specimen from Silsbee, Imperial County, 
California, (referred 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 extreme southeastern Arizona have fewer. 
Indeed, some of the latter have so few as to indicate inter- 
gradation with the gopher snakes of New Mexico which 
Ruthven has referred to P. c. sayi but which may possibly 
