LACERTILIA 245 



Multiplication. — The egg-laying lizards deposit their eggs 

 in the sand or soil, except the Iguanidse, which lay them in hol- 

 low trees. Many lizards are viviparous. The male is larger 

 and more brightly colored than the female. 



Lizards, as well as amphibians and snakes, find the ocean a 

 barrier to their progress, but lizard's eggs have in some way l)een 

 carried to oceanic islands. 



All are harmless except the Gila monster (Fig. 200), of the 

 Gila River region, which is the only poisonous lizard known. The 

 specimen in our laboratory is about 17 inches long, black, and 

 mottled with orange. Its only sound was a hiss, which it gave 

 when disturbed. 



Fig. 201.- — Glass snake {Opheosau'rus ventral' is). The tail is twice the 

 length of the body, and breaks off at the slightest blow. When broken off 

 it grows again. (From Baskett and Ditmars, "The Story of the Amphib- 

 ians and Reptiles," D. Appleton and Co., Publishers.) 



The Skinks. — This family {Scin'cidoe) is represented by the cosmopolitan 

 blue-tailed lizard common east of the Rockies as far north as northern 

 Indiana, and by the ground lizard of the Southern States. 



Cnemidoph'orus, a very little active brown lizard streaked with yellow 

 and black, is found from Connecticut to Virginia and from Wisconsin to 

 Mexico. In this family {Tc'idce) there are over one hundred species dis- 

 tributed throughout South and Central America and the warmer parts of 

 North America. 



The "glass snake" (Fig. 201), our representative of the family An'guidce, 

 has a long brittle tail. Its brittleness is due to the fact that not only are 



