114 3. IGUANID& 



cage, however, they scramble around in a lively manner, 

 their lighter colors begin to show, and they snap up meal 

 worms eagerly. 



They are good feeders, quite hardy, and are very gentle, 

 never offering to bite." 



Those which I have observed have always been on the 

 tops of boulders, and when caught have been very gentle 

 and tame, never attempting either to bite or to escape. As 

 may be seen in the photograph of a pair, the females differ 

 from the males in having but few dark spots on the throat. 



Ditmars, writing either of this or the eastern subspecies, 

 states that smaller lizards are not safe in a cage with them. 

 They devour fence lizards, horned toads, and even young 

 snakes, as well as grasshoppers, crickets, mealworms, and 

 small flowers and tender leaves. They dig hollows in the 

 sand under stones. A captive female laid 2 1 eggs early in 

 August. The eggs measured about 16x11 mm. and were 

 covered with a thin, soft membrane. Ditmars also states 

 that these lizards, when at full speed, sometimes raise the 

 body, forelimbs and tail, and run for many feet on the 

 hind legs alone. 



By Mr. Raymond Cowles: "These lizards were found on 

 the rocky hill-sides and were very active and rather shy. 

 Their strong jaws and great speed fit them for the preda- 

 ceous life which they lead. In the largest specimen was found 

 an eight inch Cnemido'phorus tigris tigris, partially digested." 



17. Crotaphytus insularis Van Denburgh & Slevin 

 ANGEL ISLAND COLLARED LIZARD 



Crotafhytus insularis VAN DENBURGH & SLEVIN, Proc. Cal. Acad. Sci., 

 Ser. 4-, Vol. XI, No. 6, 1921, p. 96 (type locality, Angel de la 

 Guardia Island, seven miles north of Pond Island, Gulf of 

 California, Mexico). 



