FISHERY RESEARCH 



323 



spawning grounds of the herring, since its eggs are laid 

 on the bottom. In this case, besides gaining information 

 from the actual catches of herring, an examination of the 

 stomach contents of other fish becomes advantageous. 

 It is known that the haddock will greedily devour herrings' 

 eggs, and the occurrence in the trawl of so-called " spawny 



9^: ! 



Fig. 61. — Chart showing distribution of plaice eggs in the North Sea in December, 



1910. The figures show the numbers of eggs per square metre surface. (After 



Buchanan-WoUaston.) 



haddock " crammed with herring spawn is a sure indication 

 that the spawning grounds are not far off. An actual 

 search for the eggs is far less fruitful, owing to the fact 

 that they lie in the crevices between stones and are rarely 

 taken in the trawl. On occasion they have been searched 



Y 



