274 NEW YORK STATE MUSEUM 



The brook trout does not flourish in water warmer than ,68°, 

 and prefers a temperature of about 50°. It is an inhabitant of 

 the cold, clear mountain streams, and will leave a region which 

 becomes polluted by mill refuse and other hurtful substances. 

 In the Long Island region and around Cape Cod, where the 

 brook trout has free access to salt water, it has the habit of 

 going to sea in the fall and remaining during the winter. It 

 then grows rapidly and becomes a much more beautiful fish 

 than many which live exclusively in fresh water. In hot 

 weather, when the temperature of the streams becomes too high 

 and lakes are accessible, trout seek the deep parts of the lakes 

 and the vicinity of cold springs. _ In streams they are to be 

 found in deep pools or in channels. They feed in spring and 

 early summer among the rapids on insects and small crusta- 

 ceans. I 



The brook trout is a nest-builder. Cavities are made in the 

 gravel, and the nest is shaped with the tail, and the larger 

 stones are carried in the mouths of the parents. After the eggs 

 are deposited, they are covered with gravel. The eggs are not 

 all deposited at one time. Spawning usually begins in October, 

 but brook trout are spawning at some locality in almost every 

 month of the year except midsummer. The egg is about i inch 

 in diameter, and varies in color from pale lemon to orange red. 

 The average yield of the female is from 400 to 600. Livingston 

 Stone has taken 1800 from a fish weighing 1 pound. 



The period of hatching will depend on the temperature, 

 ranging from 165 days in water of 37° to 32 days in water 

 of 54°. The yolk sack is absorbed in from 30 to 80 days, and 

 after its absorption the young fish begin to feed. The rate of 

 growth will of course depend on the amount of food consumed. 

 In artificial culture yearlings, according to Mr Ainsworth's esti- 

 mate, will average 2 ounces; fish of two .years 4 ounces; of 

 three years, 8 ounces, and of four years, 1 pound. 



The value of the brook trout as a food fish and its game quali- 

 ties are so well known that I need' hardly refer to them here. 



The brook trout is well adapted to domestication in aquarium 

 tanks; it soon overcomes its fear of moving objects, takes its 



