34-0 3. IGUANIDJE 



band extends about from the shoulders to the root of the 

 tail. Along the dorso-lateral region from the neck to the 

 base of the tail, on about the third or fourth row of scales 

 from the mid-dorsal line is a more or less definite longitudi- 

 nal light stripe of pale greenish yellow, most distinct on the 

 neck. The sides are variously marbled and clouded with 

 dark brown, blue, greenish yellow, and black, without any 

 very evident tendency to form narrow dark lines parallel to 

 the keels of the scales, such as are seen in S. zosteromus. 

 There is a large black blotch in front of the shoulder, usually 

 edged with greenish yellow. The upper surface of the tail 

 is light yellowish or brownish olive, often with rather indefi- 

 nite dark brown cross-bands. The lower surfaces of the 

 body, arm, and thigh are black, more or less marbled with 

 deep blue, a portion of the center of the belly and chest being 

 yellowish or bluish white. The central gular region is black 

 or very deep indigo, with paler blue streaks along the centers 

 of the scales. The lower surface of the tail is yellowish 

 white, sometimes more or less clouded with grayish brown. 

 Adult females are colored like the males above, but have 

 much less blue and but little black below. 



Snout to back of 



interparietal 20 19 20 21 22 23 



Fore limb 50 45 51 49 52 54 



Hind limb 74 69 76 76 81 85 



Base of fifth to end of 



fourth toe 28 25 29 29 28 29 



Remarks. Specimens from Cerros Island agree per- 

 fectly in coloration with a large series from Ensenada. 

 These specimens differ from S. zosteromus in having mid- 



