212 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



seine. The smallest littoral cod fry could always be 

 retained by this seine. 



With this seine the Sandnes and the Stole fiords 

 were examined in July (respectively 10 and 7 hauls), and 

 September-October (respectively 21 and 20 hauls). The 

 hauls were first made in 1904 and repeated in 1905. 



In the Kristianiafiord 28 hauls were made in August, 

 1904 and 1905. All the hauls were made as far as possible in 

 the same places and in the same manner in both years. 



The occurrence of spawning cod was studied by 

 collecting statistics from the fishermen. The occurrence 

 of pelagic cod eggs and larvae in the fiords and the 

 Skagerrak was studied by making fortnightly tow- 

 nettings in. the following manner. A small motor boat 

 dragged a circular net (1 m. diam.) of silk gauze for five 

 minutes. The net was buoyed up so as to fish within a 

 certain distauce of the surface. In this way the net was 

 towed 0, 2, 5, 10, 20 metres distance of the surface. The 

 distance covered by the boat at each tow-netting was, by 

 means of repeated experiments, proved to be about 250 

 metres. The occurrence of post-larval cod was studied 

 by means of larger nets dragged for hours, and also by 

 hand-nets. 



The hydrographical changes in the Saiidnesfiord the 

 Sondeledfiord and the Skagerrak were investigated by 

 means of taking fortnightly traverses of the waters in 

 question. Also direct current measurements were 

 occasionally done with the Ekman current meter, and also 

 with other apparatus. 



These investigations have given a series of facts, 

 which in my opinion justify the conclusion that the 

 adding of artificially hatched cod larvae is incapable oj 

 influencing the natural stock of fry, even in very small and 

 limited waters, to a perceptible degree. 



