﻿35 



We may easily in tables X & XI as also in tables I & II (in Beret- 

 ning Biol. St. HI) with respect to Pleur flesus & limanda find something 

 which may be called the constant curve (see the table p. 32), that of Pleur. 

 limanda reaching from c. 8 — 12 (13 1 /.,) inches, that of Pleur. flesus from 

 c. 10 — 14%. The latter, however, is much more common (see table) than 

 the former, and by glancing over the headings of the columns we shall see 

 that the curve of Pleur. flesus is found almost exclusively in the fjords, the 

 Belts, and the Baltic Sea, rarely in the open Cattegat where Pleur. flesus 

 goes only in the breeding- time. 



As to Pleur. limanda' the curve certainly occurs in the open Cattegat, 

 the proper dwelling-place of this fish, but very rarely only compared to the 

 great numbers of younger fish; but off the mouths of Mariagerfjord and 

 Limfjord (near the shores consequently), in the Lesser Belt at Fa?n0, and in 

 the little seas around Sainse the 3-group plays a greater part. All these 

 places are so situated that fishery with plaice-seine seldom, if ever, is carried 

 on there. At Fsena, however, the plaice-seine was introduced in 1891. The 

 open parts of the Cattegat, particularly north of Grenaa-KuUen, are as it is 

 well known the proper place for this fishery. 



On the other hand, it must be owing to emigration, evidently, that 

 the 3-group of Pleur. limanda & flesus is not found more numerously by the 

 frequent explorations in the Baltic Sea east of Falster and south of Sealand. — 



I have worked very much in order to find the situation of the con- 

 stant curve with respect to the plaice (see table II — VIII). Table I, which 

 shows the fishermen's takes, and often represents the single big fishes picked 

 out of a great number of specimens, can from this reason not be employed 

 for this purpose. 



It will be in vain in these seven tables to look for something like a 

 decided 3-group; the nearest approach to it is found in the Great and the 

 Lesser Belt and in the Baltic Sea, and the group is here generally either the 

 result of long time's fishery (Kjerteminde, Fama), or it is not very numerous, 

 as in the Baltic Sea (or perhaps, in part, not so old as it has been supposed to be). 



It is remarkable that no such 3-group can be pointed out in the Cattegat 

 (and the Limfjord); and the fishermen have told me (and proved also in 

 deed) that they too have been unable to do so, in March 1892 (table VI, 

 column 8), though the whole fishing-fleet searched most eagerly; yet, after 

 all, it is seen in table I that large fishes are to be found in the Cattegat 

 in smaller numbers. 



When, therefore, the 3-group is missing in the Cattegat, the reason 

 must be that the large plaice are not numerous enough to show the same; 



