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thein iiear Bornholui. Tliere is uo reason to doiibt tlien tliat tlie plaice 

 produce fecundated eggs as far east as Bornholm, and perhaps still t'arther; 

 nor did auybod}' ever doubt it. But the question is: What hecomes of these 

 eggs? Do they die avvay? Do ihey drift away? For of the Imge miilti- 

 tudes 110 corresponding qitantities of fry remain in the Balde Sea proper; at 

 any rate not of fry that has passed thronyh all the pelagic stages, and stay 

 near the hottom. 



Of pelagic youug plaice only very few have liitherto been found east 

 of Gedser. The Poseidon' s three expeditions in 1903 gave ouly 18 in Ihe 

 Baltic Sea, against more than 200 fiounders and commou dåbs together, 

 and persoually I have, in 1903, fouud only very few pelagic plaice, but as 

 well east as west of Gedser. To throw more light on the quautity of these 

 larvæ, these investigations, therefore, must be coutinued in March^May 

 with suitable ap[)aratus; the coramon pelagic nets are not well adapted for 

 the purpose. A youngfsh-traui which I have constructed and employed already 

 for several years from the Sallingsund, has a far greater fishing-capacity. 

 Dr. Johs. Schmidt, who employed it with great profit in Iceland, 1903, will 

 in another work give a description and a picture of it. I shall here mention 

 onl}', that it is a sort of small otter-trawl made of cheese-cloth or "stramin"', 

 whatever you will call it, aud raay be employed on somewhat deeper water, 

 in the very mass of water as well as near the bottom, to catch the fry be- 

 longing to the bottom-stage. ^) 



On the whole, there seems to be, in the pelagic life of the plaice, some- 

 thiug which has hitherto remaiued unexplained. Its larger pelagic fry has 

 been found nowhere in very great numbers, not eveu near Iceland where 

 young gadoids and other pleuronectids have been taken in multitudes. Yet 

 we should suppose it must have a long pelagic existence, since the eggs 

 occur in the Baltic Sea already before the beginuing of winter, while the 

 little young ones belonging to the bottom-stages are not to be found till 

 the end of spring. 



Owing to this circumstance we oannot vevy well, at the present stage 

 of our knowledge, use the few finds of the pelagic fry of the plaice in the 

 Baltic Sea for quantitative determinations; for this purpose a'e had better itse 

 the hottom-stages (the 0-group), as they are found in great numbers in many 

 placcs, and as it is easy to catch them and determine them. 



We do not know at all, for instance, if the Ogroup which occurs in 

 the Baltic Sea in June, comes from eggs that are shed in the Baltic Sea. 



') As to the fishing-capacity of thi.s yoiingtisli-trawl I shall sav only that, west of Ærø, lu 

 the western part of the Baltic Sea, on 20 fathoms of water, May 15., 1902, on soft clay 

 l)Ottom, I caught in one haul which lasted 10 minutes, more than 1000 }oung ones of 

 Lnmpenns lampctriformis, between '/„ — 2 inches long, as also several hundred of two 

 larger groups, respectively 3—5'/, inches ami b\'.^ — 8 inches long, besides some still larger 

 speciraens. I had not known before that this lish is n)ie nf the coiiimonest on deeper water 

 in the western part of the Baltic .Sea. 



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