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air, would put their mouths to a knot-hole to breathe. 

 If there are springs enough, trout will live in waters the 

 body of which reaches a higher temperature than seventy- 

 five. So also, a strong rush of water as with a cataract 

 or rapids, will enable them to endure greater heat than they 

 could otherwise stand. Still it is not safe to subject any 

 of the eastern salmon or trout family to a permanent 

 temperature higher than 65. Salmon trout suffer most 

 and die the first, at least when they are confined in a 

 limited space with a small flow of water. 



The first point in fish culture is to obtain the spawning 

 fish in proper condition, for if the eggs are not mature or 

 ripe, as it is usually called, not only are they useless, but 

 the effort to extract them will kill the parent. Fish 

 breeders who make the cultivation of trout a business, 

 and there are many in this country, keep on hand in suit- 

 able ponds a supply of large fish. These are taken from 

 the rivers which they are ascending to spawn, and are 

 kept over from year to year. Connected with the ponds 

 in which they are confined, is a race way, or long narrow 

 trough which has a gravelled bottom, is covered with 

 boards to exclude intrusive eyes, and in every way is 

 made as attractive a nesting spot to the fish as possible. 

 Into this they will proceed of themselves when they are 

 ready to perform their allotted act of reproduction, and 

 the breeder awaiting his opportunity, places a net at the 

 mouth of the race and frightening them in, selects such 

 as are ready for manipulation. 



When in a perfectly ripe condition, the eggs lie free in 

 the ovaries in the abdomen, and may be extruded by a 

 gentle pressure downward along the sides of the fish, 

 They are caught in a basin and are vitalized by coming 

 in contact with the milt from the males, for the fish male 

 and female are stripped indiscriminately into one common 



