THE REPTILIA 



321 



The common lizards of the eastern and central United States 

 are called skinks (Fig. 199). Young skinks have a blue tail and 

 black body, with five long yellow stripes on the sides. The adult 

 females retain these colors, but the males acquire a bright red 

 head and a dull, olive-brown body. 



Fig. 15 



• Skinks. 



(Photo, of living animals furnished by American Museum 

 of Natural History.) 



The only poisonous lizard in this country is the gila monster 

 of Arizona and New Mexico (Fig. 200). This reptile is about 

 one foot in length and heavy bodied. Its bright red and black 

 colors make it quite conspicuous (warning coloration, see p. 

 30), but its poisonous nature is an excellent protection from 

 enemies. Gila monsters are, as a rule, not harmful to man. 

 Their grooved poison teeth (fangs) are in the lower jaw so the 

 animal must turn over on its back before the poison will flow 

 down into a wound. 



