The Spotted Lizards; Zebra-tailed Lizards 



THE ZEBRA-TAILED LIZARD 



Callisaiirus 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 — gahhii (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 J " 



Width of Head ^ " 



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- 

 derfuUv active creature, running with such speed that the human 

 eve 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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