PRESERVATION OF THE SPECIES 179 



3. What two general types of postembryonic develop- 

 ment as determined by the amount of the food supplied in 

 the egg ? 



C. Protection and Care of Young 



Library Exercise 

 Materials. ' 



Books and diagrams showing as many methods for the 

 care of young as possible. 



Obsefvations. 



1. To what extent is care given to the eggs and young 

 in the case of fish ? Is the number of eggs large or small ? 

 Contrast this condition with that of the robin. What gen- 

 eral conclusion is suggested .' 



2. Describe the egg-laying habits of five or more of 

 the following : grasshopper, cecropia moth, tussock moth, 

 leaf miner, case bearer, leaf roller, sphinx moth, gall insects, 

 ichneumon flies, spiders, earthworm. How is the develop- 

 ing animal protected in each case ? How is food assured ? 



3. Contrast the method of the honeybee and the solitary 

 wasp as to the method of caring for and feeding the young. 



4. Describe the nests of five or more of the following : 

 spider, honeybee, bumblebee, paper wasp, mud dauber, 

 digger wasp. 



5. Describe the nests of the following : stickleback fish, 

 sunfish. 



6. Describe the nests of ten birds common to your 

 neighborhood. 



7. Describe the homes of the following : woodchuck, 

 mole, squirrel, rabbit, muskrat, prairie dog, beaver, bear. 



8. In case of birds which of the parent birds builds the 

 nest and cares for the little birds ? 



