Vot. IIT] VAN DENBURGH AND SLEVIN—ARIZONAN REPTILES 429 
received. The lighter specimens from Cave and Oak creeks 
make us doubt the wisdom of using a distinct name for these 
snakes. Crotalus oregonus probably occurs in Arizona only 
at considerable altitudes. 
82.—Crotalus cerastes Hallowell 
This rattlesnake was found by us near Yuma, where five 
were secured. 
No. 33450, March 15, 1912, adult, found coiled in the 
mouth of a hole under a cactus.—Scale rows 21, gastrosteges 
145, anal entire, urosteges 21, none divided, supralabials 12- 
12, infralabials 13-13, preoculars 2-2, postoculars 3-3 
loreals 1-1. 
No. 33448, March 17, 1912, young, found crawling under 
a bush.—Scale rows 23, gastrosteges 139, anal entire, urosteges 
21, five divided, supralabials 12-12, infralabials 12-12, pre- 
oculars 2-2, postoculars 3-3, loreals 1-1. 
No. 33449, March 17, 1912, young, found coiled in the 
mouth of a hole-—Scale rows 23, gastrosteges 143, anal en- 
tire, urosteges 23, one divided, supralabials 13-13, infralabials 
13-13, preoculars 2-2, postoculars 3-3, loreals 1-1. 
No. 33654, Sept. 16, 1912, adult, caught on the desert at 
night—-Scale rows 21, gastrosteges 146, anal entire, urosteges 
15, one divided, supralabials 12-12, infralabials 13-13, loreals 
1-1. 
No. 33655, Sept. 12, 1912, young, found under a tin can on 
desert.—Scale rows 21, gastrosteges 146, anal entire, uro- 
steges 16, two divided, supralabials 13-13, infralabials 13-13, 
preoculars 2—2, postoculars 3-3, loreals 1-1. 
No. 33448 contained a Uta stansburiana, while No. 33449 
had eaten a Cnemidophorus tigris. 
83.—Crotalus mitchellii Cope 
Two bright red specimens of this species were secured by 
Mr. Carlson at Cave Creek, Maricopa County: No. 17 540 on 
April 16, and No. 20814 on May 25, 1910. 
No. 17540 has scale rows 23, gastrosteges 163, anal entire, 
urosteges 18, none divided, supra ible 15-15, infralabials 
14-16, preoculars 2-2, postoculars 3-3. 
No. 20814 has scale rows 25, gastrosteges 169, anal entire, 
urosteges 21, three divided, supralabials 15-17, infralabials 
