72 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



fossil of the valley of the Saint Laurence and of certain portions of 

 Northern En rope. 



The occurrence of fossil fish in immense numbers in certain geologi- 

 cal formations has been a subject of much interest to the geologist and 

 naturalist, and many hypotheses have been promulgated in explanation 

 thereof. It is not at all probable that the ordinary casualties happen- 

 ing to fish would produce anything like the phenomena in question. 

 It is believed that very few fish die of old age, the incidents of life in 

 the sea being such that whenever any animal loses the ability to care 

 for itself some enemy is ready to devour it. The accumulations referred 

 to, found at Monte Bolca in Sicily, in Syria, in many parts of the 

 United States, and elsewhere, probably result either from some mys- 

 terious disease attacking the fish in large bodies, or from some physical 

 cause. There is but little evidence to prove the existence of serious 

 epidemics among fish in the sea, although such an occurrence is not at 

 all improbable. Even here, however, it is likely that there would be 

 enough scavengers to devour the dead and dying almost as rapidly as 

 they succumbed to the baleful influence. 



One of the methods by which fish are destroyed in great quantities, 

 and yet kept in a condition favoring their ultimate preservation, as in 

 rock strata, consists in the sweeping of large schools, during storms, 

 into low, shallow basins at the edge of the sea, where, of course, death 

 will very soon ensue. The gradual concentration, however, of the water 

 by subsequent evaporation, answers the purpose of a slow and careful 

 salting of the fish, so that for a considerable time after the basin is 

 dry the fish remain in a good state of preservation. If, as is probably 

 often the case, sand and mud are swept in with the fish, and this is 

 repeated at short intervals, a succession of strata with skeletons of 

 fish and other marine objects may result. 



A case of this kind has been mentioned to me by Lieut. Z. L. Tanner, 

 U. S. N., who noted the phenomena during the cruise of the United 

 States steamer Narragansett in 1872, at Christmas Island. The surface 

 of the shallow basin inside of the beach was occupied by many hun- 

 dreds and even thousands of fish, varying in length from a few inches 

 to three or four feet, and preserved in perfectly good condition, the thor- 

 oughly cured flesh being, however, too strongly salted to be palatable. 



F. — The natural food of sea fish. 



The vegetable kingdom at sea, as well as on laud, constitutes the 

 starting point of all animal life, and whatever may be the extent to 

 which animals devour their fellows, whether as adults, embryos, or eggs, 

 there is no doubt that without the presence of plants iu some form or 

 other and their assimilation, the existence of ani mal lifein the sea would 

 be an impossibility. It is less easy, however, in the water than on the 

 land to see the connection between the two kingdoms in this respect, 

 especially as the most important element of the vegetable division is in 



