300 FIRST YEAR COURSE IN GENERAL SCIENCE 



the little animals begin to seek their own food. Only a very 

 small proportion of the eggs deposited ever hatch, because 

 large numbers of the eggs are food for other animals. Of 

 those that hatch, only a small percentage lives to reproduce, 

 because the young become the prey of other animals and 

 man. The shad lives upon small organisms, vegetable and 

 animal, and the bluefish eats young fish, even its own kind. 

 In order to preserve wild game, it has been found neces- 

 sary to make laws prohibiting the hunting of animals at cer- 



FIG. 158. EGGS 



Figure A is a cluster of eggs of a salamander; B, eggs of a frog. These 

 eggs are surrounded by a transparent jelly-like covering. They float in 

 the water of ponds and swamps until hatched. Figure C is the egg of a 

 bird; D, eggs of a katydid. 



tain times in the breeding season. At that season, usually 

 spring and early summer in northern latitudes, fish come 

 from the ocean into the rivers and birds go to cool climates, 

 seeking places to deposit their eggs. The United States 

 Bureau of Fisheries studies the habits of fishes and the 

 relative food values of different fishes and recommends the 

 making of laws for the protection and artificial hatching of 

 food fishes. The Department of Agriculture provides for the 

 study and protection of useful birds. Larger game may 

 safely breed in public forest reservations. 



350. How Fishes Take Food. A fish has no structures 

 for grasping its food, except teeth. The teeth are usually 

 small, sharp, and numerous, well adapted for holding 



