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fish much for plaice here (i. e. east of Sealand and Falster), perhaps may 

 be indicative of the emigration of the larger fish from these seas. 



In the Great Belt at Kjerteminde (and in the Lesser Belt) (see table II) 

 a 3-group of ripe fish, however, dues not seem to be rare.' [and at any 

 rate at the first place (Kjerteminde) it is far more abundantly represented 

 than the 2-group, which seems to be almost quite missing here; for table 

 II. column 9, gives, according to my experiences, a good picture of the 

 numerical relations within the two groups, as they are in the Belt. Are 

 these ripe plaice really to represent the majority of ripe fish emigrating 

 from the Baltic? fish, then, which should have immigrated to the Baltic 

 Sea from the ( 'attegat and the Belts when they were young? 



Their size might very well agree with this, and nothing that I know 

 of plaice-fishing in the Belts speaks against it — on the contrary. The 

 sudden appearance of the plaice in these seas and their sudden disappear- 

 ance, phenomena which yearly return, agrees very well with such a mi- 

 gration. — This matter must be further elucidated by future investigations. 



It is originally Professor V. Hensen at Kiel to whom I am indebted 

 for the thought of such an emigration from the Baltic Sen. G. Winther at 

 his time has set forth a somewhat resembling supposition with regard to the 

 herring in the Sound. 



When the 3-group in the seas around the isle of Fuueu seems to 

 maintain itself better, it is easily explained by the natural condition of the 

 seas (stones, zostera, etc.) which makes it more difficult here than in the 

 ('attegat to fish up with plaice-seines; partly will these plaice, on account 

 of their smaller size, not repay greater exertions and expenses; finally, they 

 have at any rate as yet been left somewhat more in peace in these 

 enclosed waters than in the Cattegat, so that great numbers of them get 

 time to be mure than three years old. They do not get time, at any^rate not 

 sufficient time, in the Cattegat as far as we can see, to reach this age. 



Resume: We are able to point out in open nature such groups of 

 plaice of various sizes, that the fish must be supposed generally to require 

 three years to become ripe. — The size at which it becomes ripe the 

 first time is subject to considerable individual variation, irrespective 

 of the influence of the sex. and we ran only point out an a$proximatt 

 overage size with which maturity is readied: this size is different in 

 the different seas, small in the Baltic, larger in the Cattegat. At certain 

 places in the seas (lor instance the Aalkek cove) the plaice is always small ; 



