110 SEA FISHERIES 



lish, Norwegian and Swedish coasts, and I am certain 

 that they play no part in the process of spawning. Does 

 this mean that there are no natural spawning-grounds ? 

 By no means : but we must clearly understand what is 

 meant by such a term. 



The eggs of the majority of edible fish are pelagic, and 

 do not come into contact with the floor of the sea. 

 Among the species commonly sent to market only the 

 herring and rays have submarine eggs. This simple fact 

 should already warn us that a spawning-ground is rarely 

 a place where eggs are laid in a great accumulation and 

 remain until they are hatched. What, then, are the 

 characteristics of a spawning-ground ? A little while 

 before spawning the flat-fish the soles, for instance, from 

 the middle of February to the middle of March assemble 

 at the foot of submerged groups of rocks, and, leaving 

 their hiding-places in the sand, commence to swim within 

 a very limited zone, after which they expel their eggs, 

 which are dispersed at the will of the currents. This, 

 then, is a second interpretation of the term " spawning- 

 ground." Here is a third. Directly they are spawned, 

 and during the entire process of incubation, the pelagic 

 eggs are carried away by the currents. In the North Sea, 

 says M. Roy, the principal current along the English 

 coast moves southward at a rate of 5 miles a day. 

 Further to the east the current bears northward at the 

 rate of one and a half miles. If, therefore, the eggs of 

 flat-fish spawned in the north are carried away by the 

 former current, they will arrive in the south in the larval 

 state, about 60 miles from the place of their origin ; and 

 once these larvae reach favourable surroundings (clean 

 sand, calm waters, a proper temperature and salinity, and 

 a sufficiency of nourishment), they settle down and begin 

 to grow. It is the same with eggs spawned in the south 



