Chap. 35 REPTILES — FIRST LAND VERTEBRATES 719 



lizards known to be poisonous, the Gila monster (Heloderma) of the Texas 

 and Arizona deserts, marked with alternate rings of black and coral pink 



Fig. 35.6. An unusual display of ribs. In the "flying dragons" 

 (Draco) of Malaya the ribs support wing-shaped sheets of 

 skin, folded when the lizard is running, spread when it para- 

 chutes. In the hooded cobras (Naja), the ribs support the 

 hood spread when the snake is excited (Fig. 35.8). (Courtesy, 

 Guide to the Reptile Gallery, British Museum.) 



(Fig. 35.1). It has a row of poison glands along the inside of its lower 

 lip, holds on like a bulldog when it bites, and chews in the poison. It has 

 a bad reputation but is so conspicuous that human beings are rarely bitten 

 by it. 



Caught by the tail a lizard immediately escapes leaving the captured piece 



New World Chameleon 



Fig. 35.7. Three well-known lizards. The new world chameleon (Anolis), about 

 6 inches long, common in southern United States, varies in color from gray to 

 green. The old world chameleon (Chameleon) may be a foot long including its 

 prehensile tail and is famous for its changes of color. The chuckwalla (Sauro- 

 malus), one foot long, is locally known in southwestern United States. (Courtesy, 

 Palmer: Fieldbook of Natural History. New York, McGraw-Hill Book Co., 1949.) 



