CROCODIl.ES AND ALLIGATORS: LIZARDS. 



117 



It is co\'crcd with a tliick leather-like skin, instead of a 

 hard shell, abo\'e the bonj' case. 



Crocodiles and Alligators. 



These Reptiles hax'c a long body, long tail, teeth set 

 in separate sockets, and a four-chambered heart. The 

 Crocodiles of the Old World have a narrower jaw than 

 the Alligator, and their teeth differ in size. Crocodiles 

 thirty feet long, live in the river Nile. The Alligators, of 



Fig. 173- — Alligator. 



the Southern States, are five, ten, or fifteen feet long, 

 and have a head shaped something like that of a 

 pickerel. The}' are numerous in sluggish streams, and 

 devour small animals which come in their way. 



Lizards. 



These animals are small, have a long body and long 

 tail, and are covered only with horny scales. 



The Six-lined Lizard, of the Southern States, is only 

 nine or ten inches long, with six yellow lines along its 

 sides and back. It is harmless, runs rapidly, and feeds 

 upon insects. The Green Lizard, of the Southern 

 States, is a smaller species which is common about 



