BRANCH CHORD AT A; CLASS PISCES: THE FISHES 285 



curved tails to floating seaweed. The pipefish (Syn- 



nat/uis fnsanti) is a sea-horse straightened out. The 



porcupine-fishes and swellfishes (Tctraodontidce) have the 



power of filling the stomach 



with air which they gulp from 



the surface. They then escape 



from their pursuers by floating 



as a round spiny ball on the 



surface. The flying-fishes (Exo- 



ccetns) leap out of the water and 



sail for long distances through 



the air, like grasshoppers. They 



cannot flap their long pectoral 



fins and do not truly fly; 



nevertheless they move swiftly 



through the air and thus escape 



their pursuers. In its structure 



a flying-fish differs little from a 



pike or other ordinary fish. 



Foi an account of the fishes 

 of North America see Jor- 

 dan's "Manual of Vertebrates, " 

 eighth edition, ' pp. 5-173 . and 

 Jordan and Kvermann's - Fishes 

 of North and Middle America," 

 where the 3,127 species known from our continent are 

 described in detail with illustrative figures. 



Habits and adaptations. The chief part of a fish's life 

 is devoted to eating, and as most fishes feed on other 

 fishes, all are equally considerably occupied in providing 

 for their own escape. 



In general the provisions for seizing prey are confined 

 to sharp teeth and the strong muscles which propel the 

 caudal fin. But in some cases special contrivances 

 appear. In one large group known collectively as the 



Goode.) 



