81 
would be manifestly unfair to the shrimping industry to 
impose restrictions, and possibly interfere with the liveli- 
hood of so many fishermen, before making those further 
investigations that are practicable, and are most likely 
to throw much light upon the matter. 
We may take the probable effect of such restrictions 
upon shrimping as have been suggested as an instance that 
will show the problems that confront us, and the kind of 
information we want. It is interesting to speculate upon 
what would be the resulting effect upon the fish and 
shrimp populations if shrimping were either stopped 
or restricted to certain months on particular grounds. 
The number of immature fishes would probably increase, 
at least for a time—possibly permanently—and _ this 
might be expected to lead to an increase in the market- 
able fishes on the off-shore grounds a year or two later. 
The great numbers of young fish at present destroyed 
would be preserved, and, no doubt, the number of shrimps 
would also increase considerably. Interesting questions 
would then arise as to whether the fish and shrimps would 
be competitors for the same food, and whether there 
would be enough for both in their increased numbers. 
Taking the plaice as an example of the young fish, we 
know that when very young it feeds mainly on Copepoda 
—we have found their stomachs crowded with Jonesiella 
hyene and other allied forms. But, after the meta- 
morphosis, the young fishes from, say, 11 to 4 inches in 
length, feed largely upon worms such as Wereis and 
Pectinaria, upon small Crustaceans such as Mysis and the 
Amphipoda, and even upon small shrimps. Later on, the 
fish adopts its proper adult food, which is Mollusca 
(mainly small cockles, mussels and allied bivalves). 
Shrimps, we know, are general feeders (using small 
Molluses and other animals, and also Algw) and 
F 
