SEA-FISHERIES LABORATORY. 9l 



when the fish had grown to an inch and upwards in 

 length, showed them to be feeding on My sis alone. 



From their peculiar structure, one would naturally 

 expect that the flat fishes would be rather sluggish in 

 their movements, and not at all particular as to the nature 

 of their food. Far from this being the case, however, 

 they pursue their food with much vigour and select a 

 special diet, as is clearly shown when one examines the 

 contents of their stomachs. The stomachs of the smaller 

 ones, from one inch up to four inches in length, captured 

 on the shores of our neighbourhood, are usually almost 

 entirely filled with My sis, a group of Crustacea that depend 

 chiefly on the power to escape capture by making sudden 

 leaps when approached by any moving object. The flat 

 fish appear to be aware of this peculiarity, as they care- 

 fully stalk the Mysis, and when they get close up make a 

 sudden spring, seldom failing to capture their prey. That 

 the young flat fish prefer living to dead food can easily be 

 seen by throwing a mixture of dead and living Mysis 

 amongst them. The fish are always on the look out for 

 food, and at once proceed to investigate any object that 

 makes its appearance in their vicinity. If the Mysis 

 swims or leaps away, then it is pursued and captured, but 

 if it makes no attempt to escape, the fish will abandon it 

 for a more lively prey. Of course, when the fish are 

 hard pressed for food they may not be so particular in 

 waiting until the object shows considerable signs of life 

 before they capture it. 



The older flat fishes, from four inches and upwards, 

 captured on the Eoosebeck Scars, usually feed on young 

 shellfish, such as Mussels, .&c, worms (Arenicola), and 

 Crabs (Garcinus). 



Shortly after the advent of the flat fishes, the young of 

 the various round fishes, such as the codling, bluiffin, sand- 



