586 REPORT OF COMMISSIONER OP FISH AND FISHERIES. 



proved by the experience of many years, and as far as I am coDcerned 

 by my owu personal observations, that during the spawning process the 

 spawuers are nearer the surface than the milters, and these latter never 

 come to the elevated bottoms after the spawners, but frequently before 

 them. With other fish the reverse is the case. The cause of it is the 

 strange circumstance that both the roe and the milt of the codfish always 

 float towards the surface of the water. The heaviest part of the egg, 

 which is the very point where the foetus begins to develop, and where 

 the small opening is found through which impregnation takes place, 

 consequently always is turned downward. In order that impregnation 

 may take place, and the tender sperm contained in the milt may enter 

 the opening in the egg^ it is necessary that the sperm should approach 

 the egg from below and not from above j and it is likewise necessary, if 

 impregnation is to take place, that the milt should be secreted at the 

 same time as the roe or before. With other fish whose spawning pro- 

 cess has been made the subject of investigations, both roe and milt sink 

 to the bottom, and that part of the egg which in the codfish is turned 

 downward is here turned upward, and the male fish must therefore wait 

 until the female fish have laid their eggs, when they take their place 

 and j)oar their milt over the eggs. The observations made by me this 

 year have, however, convinced me that the codfish is not the only excep- 

 tion to this general rule ; for, as far as I could observe, the spawning pro- 

 cess of the haddock {Gadus ocglefinus) is very similar to that of the cod- 

 fish, and in the Lolfoden Islands takes place about the same tinic; and 

 later I obtained, by means of a fine gauze net, roe of three uilierent 

 kinds of fish, which was floating about near the surface. 



During a zoological excursion which I took this summer along our 

 Southern coast, I was fortunate enough to witness the mackerel fisheries, 

 which were going on at this time. I here met with similar facts. The 

 mackerel, which about this time approach the coast in dense, schools in 

 order to spawn, do not lay their eggs on the bottom. Their eggs, which 

 have a beautiful Clear oil-bladder at their upper end, are easily recog- 

 nized, and float about near the surface of the water exactly like the eggs 

 of the codfish, driven hither and thither by wind and waves. I also here 

 found eggs of different other fish floating about, and I succeeded in 

 hatching some of these, without, however, being able to ascertain to what 

 kinds of fish they belonged. From all these observations it seems to bo 

 clear that these peculiar features of the spawning process, at least as far 

 as sea-fish are concerned, are rather the rule than the exception. 



I had intended to make further investigations of the spawning of the 

 codfish, but was unfortunately prevented by the fearful and continuous 

 gales which soon after my arrival visited our Northern coasts, and which, 

 with scarcely an interruption, lasted all during the following month, 

 doing great damage to the fisheries, as the fishermen were prevented 

 from reaping the rich harvest which under favorable circumstances 

 would certainly have come to them. I felt sure, however, and expressed 



