36 
SECOND BOOK. 
are many kinds of snakes, and their sizes vary very 
much. With some of them the bite is poisonous. 
The huge boa-constrictor, which coils itself round 
its victims, the deadly rattlesnake, and the fierce 
crocodiles and alligators are very dangerous to 
man ” 
AMPHIBIANS. 
1. “ You have not said anything about the frog,” 
said William. “ Is it not a reptile?” 
The Toad. 
“ No,” replied Mr. Johnson, “ it belongs to the 
next class of backboned animals, and differs in a 
striking manner from any reptile, as I will presently 
explain. The animals of the frog class agree with 
