Domestic Haunts of Exocetus 227 



the water. The bladders, of course, are kept full 

 of air while the fish is on the wing, but the moment 

 it touches the water they are deflated, allowing the 

 fish to plunge as rapidly as it wishes to the limit of 

 its depth, which is not very great. These bladders 

 are an excellent substitute for the air cells within the 

 bones of birds, and make of the fish a veritable bird 

 while on the wing. 



The spawning place of the Exocetus, in the North 

 Atlantic, at any rate, is among the floating weed in 

 the Sargasso Sea, the breeding place of so many sea 

 denizens. Here I have often seen masses of ova 

 large enough to fill a flour-barrel, and looking exactly 

 like bunches of white currants, colour, size, and trans- 

 parency all lending themselves to the illusion. No 

 doubt whatever can attach to this statement, because 

 the tiny fry with the yelk fastened to it still by the 

 umbilicus were also often hauled up, and even to the 

 naked eye were recognisable at that early stage as 

 Flying-fish. But I am quite conscious that the question 

 of the breeding-places of the Indian Ocean and Pacific 

 Flying-fish is still a moot point. No one can imagine 

 the Flying-fish migrating such vast distances as would 

 be necessary if all of them bred in the North Atlantic. 

 I should, however, suppose that they find, in all oceans, 

 submarine forests of seaweed in the immediate vicinity 

 of steep-to land where they can spawn, and amid 

 whose dim intricacies their young descendants may 

 be reasonably safe from the majority of their enemies. 

 This sheltering of young fry is undoubtedly one of 

 the chief ends, if not the chief end, subserved by sea- 

 weed all around the world. Without such shelter it 

 is hard to imagine how any of the helpless fry would 

 survive the attacks of their countless voracious enemies, 

 the worst, perhaps, being their own relatives. 



