The Spotted Lizards; Zebra-tailed Lizards 



THE ZEBRA-TAILED LIZARD 



Callisaurus draconoides, (Blainville) 



Head small and flattened. Limbs very long; the hind 

 leg applied forward reaches to or beyond the snout ; tail flattened. 



Colouration. Grayish, dotted with white; two rows of 

 angular, or V-shaped blotches on the back, fusing into angular 

 bands on the tail. 



Abdomen white, with a bluish patch on each side; each 

 blue area contains two, sometimes three, ink-black bands. Lower 

 surfaces of the tail of male specimens white, with black bars; 

 the female lacks these bold markings, or they are but little evident. 



The colouration is much like that of the Texas Zebra-tailed 

 Lizard, Holbrookia texana, but the present species may be easily 

 told by the exposed ear drum tympanum. 



Several varieties have been recognised gdbbii (Cope) and 

 ventralis (Hallowell), but their varietal characters are not strik- 

 ing enough to appeal to the student. It should be remembered 

 that the ear drum at once separates this lizard from all the species 

 of Holbrookia. 



Dimensions. Total Length 5f inches. 



Length of Tail 2^ 



Width of Body 



Width of Head T \ " 



Length of Head ^ " 



Distribution. Western Texas to California ; Lower Cali- 

 fornia; northern Mexico. Principally abundant in the desert 

 regions of eastern California, Arizona, southern Nevada and 

 southeastern Utah; in these areas it is the most common of the 

 various species of lizards. 



Habits. Like most of the terrestrial lizards this is a won- 

 derfully active creature, running with such speed that the human 

 eye can barely follow it. It usually curls the tail over the back 

 when running, showing the vividly marked under-surface. Some- 

 times it runs for a short distance on the hind feet, a habit al- 

 ready .explained in connection with the species of Crotaphytus. 

 The food seems to consist partly of insects and of small blossoms 

 and tender leaves. 



The Genus Uma: Four species have been named. All 

 seem to be rare. The genus differs from Callisaurus in a peculiar 



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