quite certain that they had not at first lived in the exact locality 
where they were caught. This lack of great activity is shown also 
by the fact that it is not very greedy in seizing the fishermen’s baits 
and is not very apt to be caught when many cod are about. 
Its food, when it first reaches bottom, consists of the small 
bottom shrimp, called Amphipods and Cumacea, as well as small 
worms. As it grows it takes larger and larger animals as food, until 
finally sand dollars, sea urchins and serpent stars are the principal 
things to be found, in its stomach, although there may be many 
other animals, such as various kinds of shrimp, hermit crabs, spider 
crabs, worms, deep sea clams, and sea squirts. Very rarely does 
it feed on other fish or smaller individuals of its own kind, doubtless 
because its feeding movements are too slow to enable it to catch 
any very active prey. The fact that large sand dollars and sea 
urchins bulk so largely in its food means that the plaice takes very 
little food away from our more important fishes, and it is therefore 
an important factor in the economy of our Atlantic waters, making 
available for our use food materials that otherwise would be lost. 
As there is usually a great abundance of food in the cold water in 
which it lives, there is little likelihood of its numbers being limited 
or its growth stunted by shortage of food. 
It is preyed upon by some of the larger fishes, such as the cod, 
halibut, and sleeper shark, but we do not know to what extent they 
decrease its numbers. It is comparatively free from parasites, 
particularly in the colder waters. In Passamaquoddy bay and the 
bay of Fundy the plaice has many roundworms in the intestine 
and body-cavity and very often minute encapsulated distomes 
between the muscle fibres, whereas in the gulf of St. Lawrence both 
of these parasites are rare. In any event none of the parasites 
found would make the fish unfit for food and no diseased fish of any 
kind were to be found. 
CLIMATE. 
We may speak of the temperature, saltness, etc., as determining 
the cHmate of the water. The plaice can stand a temperature as 
low as any to be found in the sea, that is, about 29° F., and one as 
high as 50° F. as in Passamaquoddy bay, but the best temperature 
for its growth is about 40° F. It is probable that a higher temper- 
ature is better for the eggs and young fry. As to the saltness of 
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