CHAPTER XIV: THE GENERA SAUROMALUS 

 AND CROTAPHYTUS 



Fine-scaled Representatives of the Iguanidce 



The Chuckawallas — Genus Sauromalus: Of the two species, 

 one is httie known; the other is a desert reptile and fairly com- 

 mon in the southwestern portion of the United States. 



The Chuckawallas are very stout, with a fine, granular 

 scalation, both above and beneath, and on the top of the head; 

 the scales on the neck are spiny. One of these lizards attains 

 a considerable size — two feet or more; the tail is short and blunt. 

 Fully adult specimens are of a dull, uniform brown. 



Definition of the Species. 



Scales of the upper surface of neck much enlarged and 

 spiny. Scales of the back terminating in a sharp point. 

 Attains a maximum length of about two feet. 



ISLAND CHUCKAWALLA, SauTomalus Uspidus, (Stej.) 



Distribution. — Has been found on Angel Island, 

 Gulf of California. 

 Scales of the upper surface of neck, small and granular. 

 Scales of the back rounded. 

 Attains a length of about fourteen inches. 

 COMMON CHUCKAWALLA, Sauromalus ater, (Dumeril). 



Distribution. — Deserts of the Southwest. 



Following is a detailed description of the common species: 



THE CHUCKAWALLA 

 Sauromalus ater, (Dumeril) 

 The largest lizard of the southwestern desert region, with 

 the exception of the Gila Monster (Heloderma). Body very 

 broad; head proportionately large. Both pairs of limbs are 

 stubby; the tail is thick, flattened (horizontally) and but slightly 

 longer than the body. 



Colouration. — Mature individuals are practically uniform 



III 



