14 GENERAL REMARKS ON THE EGGS OF MARINE FISHES. 



shore waters, the latter the deeper water, as in our own country 

 (viviparous " Norway haddock "). The large number of species 

 in each family showing this condition on the west coast of 

 America would point to it as the most favourable for their 

 survival. It is probable that this habit was slowly acquired, 

 those having the tendency best marked being enabled to leave 

 a larger number of young, so that their chances of continuing 

 the race were greater. 



Divisions of Eggs of Food-fishes. The eggs of the bony 

 food-fishes (Teleosteans) may conveniently be divided into 

 two great divisions in accordance with their structure and 

 environment, viz. (1) those which are deposited on the ground, 

 usually called demersal, and (2) those which float about in the 

 water, and are termed pelagic. In the former group, viz. that 

 of the demersal ova, only the herring, the sand-eel, and the 

 wolf-fish (catfish) are conspicuous, while the large majority of 

 the food-fishes have pelagic eggs ; such as all the cod-tribe, 

 flounders and gurnards. No very evident connection exists 

 between the habits of fishes and the condition of the eggs. 

 Thus the pelagic herring — one of the most prolific of marine 

 fishes, and one still as abundant as ever, notwithstanding the 

 enormous efforts of man to compass its destruction — has a 

 demersal egg, deposited in masses on the bottom, while its 

 congeners the sprat and the pilchard have pelagic eggs. The 

 ground-loving frog-fish has pelagic eggs, but the wolf-fish 

 which likewise haunts the bottom has large demersal eggs. 

 The wandering cod-tribe and the race of sand and mud-loving 

 flounders have each buoyant pelagic eggs, which rise to the 

 surface of still sea-water in a vessel like globules of oil. It 

 would indeed be a difficult task to predicate from the habits of 

 a fish the nature of its eggs, since forms frequenting the same 

 region, such as the sand-eel, armed bullhead, weever and 

 dragonet, have eggs totally different in nature, the eggs of the 

 two former being demersal, while those of the latter are pelagic. 



Pelagic and Demersal Eggs. But whatever may be the 

 cause of this essential difference in the eggs of the marine 

 fishes, and more especially the food-fishes, there can be little 

 question that the pelagic character leads to the di.spersion of the 



