NATURAL HISTORY STUDIES 



the change takes place in from twenty-four to forty- 

 eight hours." 



Given horns and scales and the mantle of in- 

 visibility, the horned lizards are safe, and we are not 

 surprised to learn that most of the different kinds 

 are represented by large numbers of individuals. 

 We can understand now why they have such a wide 

 geographical range from Canada to southern Mexico, 

 and from the Mississippi to the Pacific coast ; why 

 they rarely bite ; why they can afford to take things 

 easily, basking in the sun and moving in a most 

 leisurely way. When an enemy comes they " play 

 'possum " ; when they are thoroughly scared they 

 seek refuge in a bush or burrow in the sand. 



Even in their burrowing they are unlike most 

 other creatures, for they work their way beneath the 

 ground head foremost. As Mr. Bryant says, " The 

 chisel-shaped head is the principal tool, the legs 

 being used almost solely for forcing the head forward. 

 A wriggling motion of the head and body serves to 

 drive the head beneath the sand and soon covers the 

 body completely with earth. A little shake of the 

 tail flings the dirt over that appendage, and the 

 lizard becomes entirely hidden. The nostrils are 

 kept either at the surface of the ground or near 

 enough to the surface so that breathing is possible." 

 Sometimes the spines are left protruding above the 

 ground like dry thorns. 



Stranger even than the circlet of horns and the 

 wonderfully perfect power of colour -change is the 

 habit of " shedding tears of blood." It was for 

 this that the Mexicans called the Phrynosome the 



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