220 3. IGUANID& 



median line. Thirty-two to 34 of largest dorsals equaling 

 shielded part of head. Dorsal and posterior surfaces of 

 thighs and posterior surfaces of arms finely granular j other 

 portions of limbs covered with scales which are smooth on 

 ventral surfaces of thighs, legs, arms, and forearms, but 

 keeled elsewhere. Caudal scales much larger above than 

 below, all strongly keeled. Femoral pores 11 to 15. En- 

 larged postanal plates present. 



Sooty black, brown, or slate-gray above, usually with 

 small, scattered pale blue or white dots, and often with more 

 or less definite vertical bars of deeper brown or black. Lower 

 surfaces blackish, gray, or almost white 5 chest and sides of 

 belly indigo, pre- and postanal regions tinged with azure. 

 There is no lateral blue blotch behind axilla, as in U. stans- 

 buriana. Chin and throat azure in male, lemon yellow in 

 female. 



Length to anus 41 4-2 43 45 46 48 



Length of tail 81 76 84 89 



Shielded part of head 9 8 9^ 10 9 l / 2 9 T / 2 



Snout to ear 9 9 10 10 9 l / 2 9 l / 2 



Width of head 8 7 8J^ 8 8^ 8^ 



Fore limb 18 17 19 21 19 17 



Hind limb 29 27 30 31 29 29 



Base of fifth to end of 



fourth toe 11 10 \2 l / 2 11 12 11 



Distribution.. This lizard, first described from speci- 

 mens taken at San Pedro Martir Mountain in the northern 

 part of lower California, has been found to range south to 

 San Francisco Island. It has been taken at San Matias, 

 Canon Esperanza, San Salado Canyon, Parral, San Antonio, 

 San Pedro Martir Mountain, San Quintin, Rosarito, An- 

 geles Bay, San Francisquito Bay, San Ignacio, Santa Rosalia, 

 Mulege, Concepcion Bay, San Xavier, San Nicolas Bay, and 



