36 



2) the fishes of tlie pure Mud-Zostera vegetation in Report I (Hol- 

 bæk Fjord) and IX (the harbour at Frederikshavn), 



o) tlie fishes of the red-alga Zostera vegetation in Report III (Fænø 

 Sound), and 



4) the fishes of the brackisli-water or greeu-alga Zostera veget- 

 ation in Report V, p. 38 (Stege) and p. 42 (Frederikssund). 



Among the auimals mentioned tliere are ouly two in reality which form 

 the object of any extensive iishery, namely, the eel and the prawn, and it niight 

 from that be concluded that the Zostera was not of special benefit to our fisheries, 

 and even, since it at times stops up the tixed nets and prevents the setting of 

 gill-nets and the like'), that it was an evil; but this is certainly an error; I eau 

 fully agree with Dr. C. G. Joh. Petersen' s sentence quoted as motto for this 

 paper. The rich Zostera vegetation in our waters is one of the prin- 

 cipal supports of our fisheries, as it must be considered a most im- 

 portaut breeding ground for the nourishment of our food-fishes. 



1) Fiskeriberetningen for 1899—1900, p. 178 and 1900—1901, p. 149. 



