Introduction. 



Modern naturalists have, loug ago already, clearly understood that the 

 investigation of nature is the first condition of scieutific progress; but it must 

 be grauted that the way in which the various countries have had their fishes 

 and fisheries investigated, has been auything but satisfactory. A few histo- 

 rical data, fetched from the investigation of the Skager Rack, will afEord a 

 characteristic example of this faet: 



When H. Krøyer wrote liis work of »Danmarks Fiske«, he knew, from 

 personal observation, no more about the fishes of the Skager Rack than what 

 tlie fishermen had observed; he had no means at all at his disposal for inve- 

 stigations of his own. As the fishermen fished only near the shore, or in the 

 surface of the water, nothing was known then about the fishes of the Skager 

 Rack proper, but the single specimens which on some occasion (in a storm, 

 perhaps) were stranded on the shores; whether they really did belong to the 

 stock of fish of the Skager Rack, or whether they had come from far aM'ay, 

 was a thing nobody knew for certain. 



When G. A. Bergh in the Swedish gunboat »Ingegerd«, in 1870, inve- 

 stigated the Northern Cattegat and Skagbanken off the Skaw, as also Koster- 

 grunden ofE Strømstad, particularly to learn whether the bottom there was 

 suitable for trawHng, cousequently just for fishery purposes, such gear was 

 employed that he caught no other fishes than young lump-fish and a few pipe- 

 fish ; the common species he knew only from the fish-market at Frederikshavn 

 or from the fishermen's boats; the crew, however, seems to have enjoyed itself 

 by catchiug cod in its leisure hours. 



When G. Winther, in 1879, wrote liis »Prodromus ichthyologiæ danicæ 

 marinæ«, uo investigations had as yet been made, for the purpose of catcliing 





