23 



the same geographical distribution seems to become noticed and admitted wilh 

 respect to more and more species; I shall only meiition that JShrenbaum in 

 his last beautiful work on "Fisclie mit festsitzenden Eiern. Wissenseliaftl. 

 Meercsunters. VI, 1904", saj's tliat the seawolf [Anayrkichas) certaiuly is 

 I'ouikI at Heligoland, but wliether it "iiberhaupt iu der Deutschen Buclit 

 laiclit, darf bezweifelt werdeu". 



What ought to be the Particular Object of Future International 



Investigations? 



To examine closely wlience tiie stock of plaice within the Skaw more 

 particularly gets its increase of young fisli, \ve must study 1) where the 

 spawniug tisli are to be met with in multitudes; 2) where their eggs are to 

 be fouud iu the greatest numbers; 3) wliere the pelagic larvæ, and 4) where 

 aud when the 3'oung fish belonging to the bottom-stages appear on the 

 sliores. I shall not discuss liere more closely how this eau best be done; 

 I only wish to say a few words as to the iuvestigation of the bottoni- stage. 



From table II, page 10, it is seen that quite small young fish are 

 found at Fæuø, station 4; at Nyborg in the Great Belt, station 7; and 

 partly at Frederiksliavn, station 1. They have been taken as small as 

 10 mm. When we find them so small, we can be pretty sure that they 

 come from pelagic fry which has lived through its last stages in the neigh- 

 bouriiig seas. But ofteu the fry is not found till later in summer or in au- 

 tumn, and then it is considerably larger (table II, page 10); in September a 

 few specimens reach 10 ctm. The currenf along the shore can now very well 

 have carried the fry fur aivay from the lilaces where it lived as pelagic fry. 

 When we have seen the fry penetrate into the Limfjord, from west to east, 

 or when we have seen what the strong currents in the Belts can carry 

 aloug of pipe-fish, gobies, eels, remmants of piants, small stones, etc, we 

 will understand to value this momentum. The younger we find the 0-group, 

 the more certain, therefore, ive may be, that tve are near the piaces ivhere the 

 pelagic young fish have lived. At any rate we must take care to keep the 

 0-group apart from the 1-group, aud we do this in the safest way by 

 measuring the fry. How much help we may get here by examiniug the 

 otoliths, I do not kuow; Apstein's results, loc. cit., do not seem to me to be 

 very probable, and at any rate they must be supported by measuremeuts 

 if we shall be able to say anything positive. I shall only point out the 

 faet that the quite tender fry has not been found in the Baltic Sea properly 

 so called aud at Bornholm ; as a rule the young fish found here are more than 

 3 ctm. I should very much wish to know if they are to be found here in the 

 first stages, immediately after their transformation. Therefore we must carry 

 out our investigations in May or June with a shrimp-net of a fabric which 

 is so closely wovon that the holes juit permit the necessary sand to pass 



