158 3. IGUANID3E 



of the blue areas, and from here the blotches run forwards 

 and upwards to the sides, the apices becoming lighter in 

 color and blending with the dark lateral markings, when 

 these are present. In females the blue patches are want- 

 ing, and the spots are represented by a pair of dusky mark- 

 ings which may be rather distinct but in most specimens 

 are not well defined. Between the bluish patches and the hind 

 limbs in the males, and in the corresponding region in the 

 females the color although occasionally white is usually bright 

 yellow, as are also the sides of the base of the tail, espe- 

 cially in the females. The ventral surface of the tail is 

 white with five to eight broad, jet black markings. These 

 markings are the continuation on the ventral surface of the 

 cross bands of the upper surface, and each of the four or 

 five distal ones are fused with a corresponding one on the 

 dorsal surface to form continuous rings; there are usually 

 one to four proximal ones, however, which do not extend 

 to the sides of the tail but form blotches on the median 

 ventral line." 



Length to anus 44 72 74 82 86 88 93 



Length of tail 59 102 98 107 117 130 



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 Desert Gridiron-tailed Lizard seems 

 to be confined to the Lower Sonoran Zone, where it usually 

 is found on gravelly or sandy plains or washes. It ranges 

 over a wide area of desert regions in eastern California, 

 southern Nevada, southwestern Utah, western and southern 



