FISHES. 565 



length ; the body is covered with triangular scales, commonly of a 

 bluish colour. They live on worms, fishes' eggs, and fragments of 

 organic substances which they find at the bottom of the sea. 



III. PHARYNGOGNATHA. 



This order contains fishes in which the inferior pharyngeal bones 

 are so completely coalescent as to form a single bone, which is 

 usually armed with teeth. Professor Miiller divides this sub-order 

 into two groups, that in which the fins are partially spinous (Acanthop- 

 terygii), and that in which the fins are soft (Malacopterygit). Of this 

 latter group we have one interesting family, that of the Scomber- 

 esocida, to which the genus Exocatus belongs. 



Flying is so much associated in our minds with the usual denizens 

 of the air, that the idea of flying-fishes seems to be a contradiction. 

 Nevertheless, some fishes possess that power, the fins being trans- 

 formed into wings, which they are enabled to raise for a few seconds. 

 These wings, however, are neither long nor powerful, for they rather 

 act the part of a parachute than wings. The distinguishing charac- 

 teristic of the Exoccetits, or flying-fish, is its pectoral fins, which are 

 nearly the length of the body, the head is flattened above and on the 

 sides, the lower part of the body furnished with a longitudinal series 

 of carinated scales on each side, the dorsal fin placed above the 

 anal, the eyes large, and the jaws furnished with small pointed teeth. 



The flying-fishes (Fig. 372) in their own element are harassed by 

 attacks of'other inhabitants of the ocean, and when, under the excite- 

 ment of fear, they take to the air, they are equally exposed to the 

 attacks of aquatic birds, especially the various species of gulls. We 

 have said that in their leap from the water their fins sustain them 

 rather as parachutes than wings, with which they beat the air. Mr. 

 Bennett's description is pretty clear on this point. " I have never," 

 he says, " been able to see any percussion of the pectoral fins during 

 flight ; and the greatest length of time I have seen this volatile fish 

 on the fly has been thirty seconds by the watch, and the longest 

 flight, mentioned by Captain Basil Hall, has been 200 yards, but he 

 thinks that subsequent observation has extended the space. The 

 usual height of their flight, as seen above the surface of the water, is 

 from two to three feet ; but I have known them come on board at the 

 height of fourteen feet and upwards ; and they have been well 

 ascertained to come into the chains of a line-of-battle ship, which is 

 considered to be upwards of twenty feet. But it must not be sup- 

 posed that they have the power of raising themselves into the air after 



