194 



SUBKI^GDOM VERTEBEATA. 



ss5. 



it so tightly that a strong man can hardly drag it loose. This 

 arrangement probably serves it for cheap and easy transpor- 

 tation, as it is not a good swimmer. 



Pleuronectidae (side-swimmer). The Flat-fish has its 

 head singularly twisted, so that both eyes are on the same 

 side of the body. This is always the upper and dark-colored, 

 Thile the lower side is white. The Family furnishes im- 



portant food fish as 

 the Halibut, Turbot, 

 Sole, and Flounder; 

 the first sometimes 

 reaching a weight of 

 six hundred pounds. 



Exoccetidae (sleep- 

 er-out). The Flying- 

 fish has large pectoral 

 fins, by which it can 

 support itself in the 

 air for a few seconds.* 

 Its brilliant coloring 

 makes it the common 

 prey of bird and fish. 



* This so-called "flight" is only the result of an impetus acquired by swimming 

 to the surface with great velocity, in order to escape its enemies. It cannot change 

 its course nor raise itself in the air, and its fins cannot be flapped like wings, but 

 serve only as a parachute. Capt. Basil Hall gives a very animated description of the 

 pursuit of a school of flying-fish by a dolphin (Coryphcena hipptiris, Coryphene, note, 

 p. 84). "The flying-fish took their flight to windward. A large dolphin, which 

 had been keeping company with us abreast of the weather gangway, and, as usual, 

 glistening most beautifully in the sun, no sooner detected our poor dear friends take 

 wing than he turned his head toward them, darted to the surface, and leaped from 

 the water with a velocity little short, as it seemed to us, of a cannon-ball. But 

 though the impetus with which he shot himself into the air gave him an initial 

 velocity greatly exceeding that of the flying-fish, the start which his fated prey had 

 got enabled them to keep ahead of him for a considerable time. The length of the 

 dolphin's first spring could not have been less than ten yards, and after he fell we 

 could see him gliding like lightning through the water for a moment, when he again 

 rose and shot upwards with considerably greater velocity than at first, and of course 

 to a still greater distance. In this manner the merciless pursuer seemed to stride 

 along the sea, while his brilliant coat sparkled and flashed in the sun. As he fell 

 headlong in the water at the end of each leap, a series of circles was sent far over 

 the surface, for the breeze just enough to keep the royals and topgallant studding- 

 sails extended ^was hardly felt as yet below. The group of wretched flying-fish, 



