210 THE FROG AS AN INTRODUCTION TO MAN 



3. What is meant by the term " metamorphosis " ? 



4. What stages of a tadpole are most like a fish ? 



5. What becomes of frogs and toads in winter ? 



6. What are the Amphibia? 



7. When do frogs lay eggs ? . Where ? 



Special Reports 



1. Artificial fertilization of frogs' eggs. 



2. The usefulness of the toad, 



3. The artificial propagation of frogs. 



References 



Hunter, Essentials of Biology. Chap. XXII. (Amphibia.) 



Elements of Biology. Chap. XXIII. 



Hodge, Nature Study and Life. Chaps. XVI and XVII. 



Chamberlain, F. M., "Notes on Edible Frogs of the United States, 

 and their Artificial Propagation." Report of the U. S. Fish Commis- 

 sion, 1897, pp. 251-261 (Part 23). 



Gage, S. H., "The Life History of the Toad." Cornell University 

 Teachers' Leaflets, No. 9, April, 1898. 



