328 3. IGUANIDA 



interparietal plate to a line connecting posterior surfaces of 

 thighs varying from 27 to 37} average, 29.2. Males with 

 enlarged postanal plates. 



The upper surfaces are yellowish, greenish, or olive- 

 brown, darker on the head. The back is crossed by broad, 

 more or less definite and irregular dark bands, some seven 

 in number on the neck and body. One of these bands is 

 darker and more definite than the others, forming a con- 

 tinuous black collar across the shoulders. This black collar 

 may have light margins. The head may show transverse 

 dark markings. The limbs are cross-barred, and the tail 

 ringed, with dark brown. The lower surfaces are yellowish 

 white, with a large blue patch on each side of the abdomen, 

 sometimes bordered internally with black. There is a dark 

 blotch in front of the thigh. The chin and throat are blue, 

 sometimes bordered behind by a blackish extension of the 

 collar across the throat. The chin may have blackish spots. 

 The blue blotches may be absent in females. 



Length to anus 47 +9 82 105 109 123 



Length of tail 61 110 123 



Snout to orbit 4 4 6 8 9 



Snout to ear --11 11J4 19 26 22 26 



Snout to back of 



interparietal 11^ W'/z 17 20 23 



Width of head . 11 11 J/^ 20 27 25 30 



Fore limb 21 20 36 42 45 50 



Hind limb 30 29 51 70 63 67 



Base of fifth to end of 



fourth toe 12 12 19 20 21 23 



Distribution. — This lizard is common in parts of Texas 

 and New Mexico, and ranges thence south into Mexico, and 

 west into Arizona. Arizona records are few and are in part 

 based upon specimens of other species (as 5. jarrovii). 



Dr. Stejneger informs me that the National Museum 

 has specimens collected by H. W. Henshaw in 1874, labeled 



