76 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



giants among the true fishes, sucli as the swordfish, the tunny or horse- 

 mackerel, &c., which in turn have their antagonists as already men- 

 tioned. 



The seals, too, devour the larger fish in great quantities ; and in turn 

 they are attacked by the cetaceaus, such as the oroa, or killer whales, and 

 other kinds especially adapted for their destruction. Again, the whales 

 are also antagonized by the killers and various species of swordfish ; 

 and, indeed, possibly with the exception of the sperm whale, there is no 

 animal in the sea but what has its foe. Man, however, presents him- 

 self as the enemy and antagonist of all the species, and is provided with 

 means for their capture. 



We have already referred to the abundance of vegetable matter in the 

 sea, and to the possibility of supplying it in sufficient quantity to serve 

 as the basis of marine animal life, and the marine zoologist will have no 

 difficulty in understanding how the countless numbers of fish in the 

 ocean obtain their food, in view of the myriads of Crustacea, of mollusks, 

 of worms, &c, which inhabit the waters. 



It is not the species that remain in or near the bottom that are of the 

 most importance, but the free swimming and floating forms that are 

 most extensively and readily devoured. While at no time does the 

 apparatus of the zoologist fail to reveal the presence of animal life, 

 even though of microscopic dimensions, at times this manifests itself in 

 bodies, the masses of which almost stagger the imagination, the sea for 

 hundreds of miles in extent being an animated mush, what with shrimps 

 and other crustaceans, salpse, and larva) of mollusks, worms, &c, a 

 bucketful of water taken indiscriminately over the entire area seems 

 filled with animal life. Nor are these organisms confined to the surface, 

 the evidence of the beam-trawl and the dredge revealing its existence 

 in equal quantities below. Various species of minute Crustacea are not 

 uufrequently thrown in masses on the beach, so as to constitute wind- 

 rows of many miles in extent, this of course being but a small percent- 

 age of what is left behind. Where these smaller animals are aggre- 

 gated in unusual numbers are generally to be found great schools of 

 mackerel, herring, whales, and other animals pursuing them, as though 

 certain definite instincts of migration influence them, or they are driven 

 in their season in a definite direction. Schools of fish follow, which are 

 thus brought more nearly to the nets of the fishermen. Indeed, generally 

 the movements of the fish are directed by the instinct of reproduction, 

 in which they aim at finding a suitable locality for the deposit of their 

 spawn, or in search of food, which they either follow or travel to meet. 



Among the inhabitants of the deep sea which serve as food for the 

 larger fishes and cetaceans are probably various forms of the cephalo- 

 pods or cuttle-fish, of which the stomach of the sperm whale frequently 

 contains large masses, proving their occurrence of dimensions far be- 

 yond those of which actual critical observation has yet been made. It 

 will, therefore, be readily understood, from what has already been 



