208 



THE ANIMALS AND MAN 



jaw, flows along the grooved teeth into the wound. A beau- 

 tiful and interesting little lizard found in the south is the 

 green chameleon. Its body is about three inches long, 

 with a slender tail of about five or six inches. The nor- 

 mal color of the chameleon is grass-green, but it may as- 

 sume almost instantly shades varying from a beautiful 

 emerald to a dark and iridescent bronze color. 



About looo living species of snakes are known. Usually 



Fig. 106. The gopher-snake, Pituophis hellona. (Photograph from life, 

 by J. O. Snyder.) 



they have the body regularly cylindrical, and without dis- 

 tinct division into body-regions. Legs are wanting, loco- 

 motion being effected by the help of the scales and ribs. 

 No snake can move forward on a perfectly smooth surface, 

 and no snake can leap. In some forms, such as the pythons, 

 external rudiments of the hind limbs are present, but do 

 not aid in locomotion. The mouth is large and distensible, 

 so that prey of considerably greater size than the normal 

 diameter of the snake's body is frequently swallowed whole. 

 The sense of taste is very little if at all developed, as the food 

 is swallowed without mastication. The tongue, which is 



