THE TADPOLE. 97 



seldom misses its aim. Collectors of insects often 

 examine the stomachs of toads, finding in them some 

 kinds of beetles the . collectors themselves have over- 

 looked. Every toad is a valuable assistant to crop 

 growers, and it should not be killed, except when 

 needed for other purposes. Upon the approach of 

 winter, frogs and toads conceal themselves either in 

 the mud at the bottom of a pond, or in a hole in the 

 ground. Here they remain all winter, without eat- 

 ing, or breathing very much. On the approach of 

 spring, they come out of their winter quarters prepared 

 for another summer's activity. Stories of living toads 

 having been found embedded in rocks, where they 

 have lain for thousands of years, are probably all un- 

 true. None have been satisfactorily authenticated. 



The Tadpole. 



1. Notice the shape of the body. In what direction 

 (laterally, or vertically,) is the tail flattened? 



2. See the mouth. Is it large or small? Has the 

 tadpole eyelids? Has it legs? 



3. Notice the intestine. Cut through the body 

 wall and examine it. How long is it? Is it 

 longer, or shorter, than the intestine of a frog? 

 Remove it. 



4. See the gills. How many? Draw. 



5. Find the heart. Trace the artery to see whether 

 it goes to the gills or to the system. How many 

 chambers has the heart? 



6. Examine a large tadpole. Which pair of legs 

 begins to grow first? What becomes of the tail? 

 What do tadpoles eat? 



7. What is the difference between toad tadpoles 

 and frog tadpoles? 



8. What is the difference between toad eggs and 

 frog eggs? 



