DISCUSSION. 



Prof. E. E. Prince (Canada). I feel again as if I ought to apologize for rising to 

 speak, at the same time I am impelled out of a sense of gratitude to Doctor Gill, which 

 all the younger workers in ichthyology and the students of fish and fisheries generally 

 feel for one who is the Nestor of the science of fish and fisheries. It is a privilege which 

 I think we shall long remember to have heard Doctor Gill on this occasion; and I 

 think that on the principle of keeping the good wine to the last it was appropriate that 

 Doctor Gill should come in even at the end of the programme. I may claim to be one of 

 the younger workers, and I have always felt that Doctor Gill was one who gave credit 

 to the young workers for anything they contributed to science. 



I do not wish to trespass very long on the time of the congress, but I feel especially 

 interested in Doctor Gill's reference to the development of the eel, because since I came 

 to this congress I have received quite a long letter from Doctor Schmidt, of Copen- 

 hagen, asking about the movement of young eels in our Canadian waters, and I hope 

 to be able to report, as indeed I have previously, certain observ-ations of my own as to 

 the migration of young eels up some of our Canadian rivers. Countless multitudes 

 ascend in the summer, especially in August, and they surmount obstacles such as 

 high falls. 



The statement that one can never prophesy the characteristics of a fish as to its 

 eggs and its young I know to be very true, and we should remember the warning 

 which I think Sir Ray Lancaster, long ago, gave embryologists, that embryology 

 was so full of surprises and wonders that we must never prophesy until we know. I 

 remember, years ago, my own experience in regard to Clupea sprattus, for I felt as 

 if all the herring family should deposit their eggs in a certain way, viz, on the sea 

 bottom, because Clupea harengtis did so; and I remember with great surprise finding 

 that Clupea sprattus, the small sprat in European waters, deposited not only a pelagic 

 or floating egg, but an egg of extreme delicacy. The egg of Clupea sprattus is the most 

 delicate and most buoyant. This is surprising when one remembers the nonbuoyant 

 eggs of the herring. Then, the fact that the smelt alSo deposits, like the Salmonidse 

 generally, not only a heav}' egg, but an egg which is attached by a kind of pedestal to 

 stones in brackish water, not a loose free egg, shows that we must investigate by actual 

 observation and by actual study the character of the eggs and spawning peculiarities 

 of every species. 



Again, the fact that the male in some species and the female in others perform 

 certain functions during the life of their young brood has a most interesting but a 

 somewhat perplexing side. I remember only last summer, just a year ago, finding on 

 the Pacific coast a fish which is well known, I am sure, to Doctor Gill, Porichthys 

 porissimus, a very unprepossessing fish in appearance, but a fish which has the peculiar 

 habit of sitting beside its eggs through development; and not only sitting by them 

 and watching them, but singing to them, and as you walk along the beach you hear 

 the peculiar cooing sound, or kind of croaking sound, which the parent fish makes 

 when sitting by her brood and watching them. What the meaning is we can not sur- 

 mise; but we find the fish singing to its young when they are actually attached firmly to 

 the underside of the rock where the female deposited the eggs. Whether it is the male 

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