50 CALIFORNIA ACADEMY OP SCIENCES. 



near the large verdigris green blotches on the sides of 

 the belly. There is a reddish orange area in front of 

 each of these green blotches. The throat is gray with 

 a half-concealed vermilion spot. 



Length to anus 44 72 74 82 86 88 



Length of tail 59 102 98 107 117 



Snout to back of interparietal 9 13 13 14 15 15 



Snout to ear 10 15 14 16 16 16 



Width of head 9 13 13 14 14 14 



Fore limb 24 42 41 45 49 46 



Hind limb 41 70 65 76 79 



Base of fifth to end of fourth toe. . . 17 31 30 33 35 



Distribution. The range of the Gridiron-tailed Lizard 

 in California is, in general, the whole southeastern part 

 of the state comprised in the Mojave and Colorado Des- 

 erts. In the north, it extends to Owen's, Saline, and 

 Death Valleys, in Inyo County; in the west, to the lower 

 parts of Antelope Valley in Los Angeles County, and 

 the top of San Gorgonio Pass near Banning, Riverside 

 County. The species has been found also at Fish 

 Springs and in a little 'island' of the desert at Oak, 

 Grove, San Diego County, and is very abundant along 

 the Colorado River. "Southern and western Nevada 

 as far north as Pyramid Lake " are also occupied by it. 



Habits. The Gridiron-tailed Lizard " inhabits the 

 open deserts and runs with great swiftness over the sand 

 and gravel beds, carrying its tail curled over its back as 

 if afraid to let it touch the hot surface of the earth. It 

 starts off at full speed as if fired from a cannon, and 

 stops with equal suddenness, thus escaping or eluding 

 its enemies, the coyotes, hawks, and larger lizards. 

 When running it moves so swiftly that the eye has diffi- 

 culty in following, and when at rest its colors harmonize 

 so well with those of the desert that it can hardly be 



