191fi ] Camp: Amphibians and Reptiles 509 



S. Sauromalus ater Dumeril. Chuckwalla. 



9. TJta stansburiana elegans Yarrow. Desert Brown-shouldered Lizard. 



10. Uta graciosa (Hallowell). Long-tailed Swift. 



11. Seeloporus magister Hallowell. Rough-scaled Lizard. 



12. Phrynosoma platyrhinos Girard. Desert Horned-toad. 



13. Xantusia vigilis Baird. Desert Night Lizard. 



14. Cnemidophorus tigris tigris Baird and Girard. Desert Whip-tailed Lizard. 



15. Sonora episcopa (Kennicott). Texas Ground Snake. 



16. Sonora occipitalis (Hallowell). Desert Burrowing Snake. 



17. Lampropeltis boylii (Baird and Girard). Boyle King Snake. 

 IS. Bascanion flagellum frenatum Stejneger. Red Racer. 



19. Crotalus mitehellii (Cope). Pallid Rattlesnake. 



20. Crotalus cerastes Hallowell. Sidewinder. 



GBNEKAL NOTES ON THE AMPHIBIANS AND REPTILES 

 OP THE COLORADO DESERT 



The most common amphibians of the Colorado Desert are toads. 

 Three hardy species of SaUentia (Bufo cognatus cognatus, Bufo 

 alvarius, and Bufo lentiginosus woodhousii) inhabit the Colorado 

 River valley, and one other species, Bufo punctata*, though not known 

 to be found along the river (south of the Grand Canon), occurs in 

 some of the desert springs, mountain canons, and stream-beds (see 

 (Stone and Rehn, 1903, p. 34, and Stejneger, 1893, p. 219). The 

 Great Basin leopard frog, Rana pipiens brachycephala, also lives in 

 and along the Colorado River. 



Recent reptiles are represented on the Colorado Desert in Cali- 

 fornia and Arizona by one species of tortoise, one gecko (Coleonyx), 

 one night lizard (Xantusia), the "Gila monster" (Heloderma) , one 

 tend (Cnemidophorus) and thirteen iguanine lizards, one blind snake 

 Hi iiii), six colubrine and two crotaline snakes. A mud turtle ( Kinos- 

 ternon) occurs along the lower Colorado River. It might be noted 

 here that Stephens (1914, p. 134) denies reports of the presence of 

 "Gila monsters" in southeastern California. Neither is there any 

 authentic record of Holbrookia or Elaps from California. The igua- 

 nine lizards include nine genera, the colubrine snakes five, and the 

 crotaline snakes two. Among the genera of iguanine lizards are found 

 herbivorous, carnivorous, omnivorous, insectivorous and myrmeco- 

 phagous forms. Most species of desert lizards live on the ground 

 among rocks or on sand and some spend their time in bushes and 

 desert trees. In comparison with the lizards, the snakes of the Colo- 

 rado Desert are few in number of individuals. 



