The Horned Lizards 



Distribution. Abundant in the desert and sub-arid regions 

 of eastern California, Arizona, Utah, Nevada and southern Idaho. 



MAcCALL'S HORNED LIZARD 

 Pbrynosoma maccallii, (Hallowell) 



The last lizard of this genus is of rare occurrence. It has 

 the longest head spines of any of those species with concealed 

 ear-drums. There are two series of spiny, marginal scales on 

 the body, the upper of which is the longer. In the central region 

 of the chin are two single rows of slightly enlarged scales. The 

 scales of the abdomen are smooth. The skin of the back appears 

 very smooth as compared with other horned lizards. 



The head spines are peculiar. There are two very large 

 central spines; only the two rear spines of the temples are large 

 this in place of the three successively larger temporal spines 

 of most species. 



Colouration. Ashy-gray; a narrow, brownish line upon the 

 back; on each side this are two rows of round, brown spots each 

 containing a paler centre, which in turn is centered with a brown dot. 



Dimensions. Total Length 3! inches. 



Length of Head and Body 2| " 



Width of Body i^ " 



Distribution. The Colorado Desert. The United States 

 National Museum has specimens from Fort Yuma, Arizona. 

 It appears to be a very rare species. 



Habits. Nothing is known of the habits. 



The desert fauna of the United States is not only distinct, 

 but highly interesting. One of the most fascinating exhibits 

 in the reptile house of the New York Zoological Park, is the 

 "desert room." Here, even the most casual observer will 

 at once note something peculiar about the lizards and the snakes 

 their pallid hues, their remarkable similarity to the sand and 

 their adaptability to the dry, loose soil, in their movements of 

 burrowing or progressing at great speed over a surface where 

 many reptiles would be clumsy. At a temperature in which 

 some reptiles thrive, these creatures of the deserts are sluggish. 

 They flourish and are most active in a heat that is practically un- 

 endurable to the human. This phase of reptile life is worth much 

 space much more than can be given to it in the present work. 



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