The Horned Lizards 



Size moderate. Horns more developed and nearly as 



long as the horizontal diameter of the eye. 

 HERNANDEZ'S HORNED LIZARD, P. douglassii, variety her- 



[nandesi, Girard. 

 Length of adult. $\ inches. 



Distribution. The Great Plains and Rocky Moun- 

 tain district generally an abundant form. 



This species is interesting in demonstrating, in all its phases, 

 the remarkable similarity of the colour of individuals to the 

 soil on which they live. It is illustrated to an extraordinary 

 degree with specimens found in areas where the soil is of an 

 unusual shade. Several specimens of the desert form ornatis si- 

 mum collected for the writer were examined with surprise;/^ 

 were distinctly pink, with white spots. A letter received from the 

 collector contained the following explanation: "The horned toads 

 sent you were taken in a region where the soil was pinkish, scattered 

 with fine white pebbles. They were very difficult to see, unless mov- 

 ing. Dr. Stejneger described specimens of the typical form from 

 the San Francisco Mountains, that exactly match in their ground 

 colour the soil and rocks, while their paler markings are perfect 

 imitations of the lichens covering the rocks. He further explains 

 that even more remarkable are the specimens collected by Dr. 

 Merriam in a black lava belt. These specimens were satiny black, 

 with rich, yellow markings even the gloss of the lava was imi- 

 tated. A female specimen of this phase and her young are fig- 

 ured in an accompanying photograph. 



Through the courtesy of D. D. Streeter, Jr., the writer 

 has received a number of living female specimens of the variety 

 hernandesi, from Wyoming. This afforded an admirable op- 

 portunity of studying the young horned lizards, which are pro- 

 duced alive and a few minutes after birth are able to scurry over 

 the ground with an agility equal to that of the parent. The 

 average brood of young among these specimens numbered ten. 

 The young creatures appeared quite smooth. Their skin was 

 soft and delicate. All of these young reptiles were born during 

 the early part of September. 



THE MEXICAN HORNED LIZARD 



Phrynosoma orbiculare, (Wiegmann) 



This species falls readily into the first group of the genus, 

 by reason of its short horns and exposed ear drums. The scales 



149 



