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REPORT OF THE COMMISSIONERS OF 



hand covered with a wet woolen mitten grasps the fish above the tail and with the 

 thumb of the other hand the operator presses the abdomen gently, with a downward 

 motion over the ovaries, holding the vent over the spawning pan ; if the fish is ripe, 

 the eggs will run freely. Very little force should be used in the operation and the 

 fish should be held close to the pan. Practice teaches the operator to distinguish a 

 ripe fish as soon as it is in his hands. The male fish is treated in exactly the same 

 manner, and the milt flows into the spawning pan with the eggs, and milt and eggs 

 are stirred together with a feather, with the tail of the fish if it is small, with the 

 operator's hand, or by gently tilting the pan from side to side. This is called the dry 

 method of impregnation because the eggs and milt are taken in a dry spawning pan, 

 instead of one partly filled with water; and by the dry process one hundred per cent, 

 of good salmon or trout eggs may be impregnated, while by the wet process (an inch 

 or two of water in the spawning pan) only from sixty to seventy per cent, are impreg- 

 nated. The eggs are quickly impregnated, within a quarter of an hour after they 

 come in contact with the milt, no matter what the temperature of the water may be, 

 and it is usually accomplished in two or three minutes. A little water is then added 

 to the pan and the eggs are left until they separate. Eggs when they come from the 

 fish are not round, but slightly shrivelled ; when fertilization takes place, the eggs 

 absorb not only zoospermes, minute organism of which the milt is composed, but 

 water as well, and during the process of absorption the eggs adhere to the pan and to 

 one another. When absorption is completed the eggs are round and plump and they 

 separate and are ready after a thorough washing to be placed on 

 the hatching trays or glass grills. In America trays are used, sides 

 and ends of wood and bottom of wire that is tarred. These trays 

 are placed in wooden, troughs containing running water and are 

 left to hatch. Trout eggs are heavy and non-adhesive and about 

 one-sixth of an inch in diameter. The average production of 

 eggs is from 350 to 1,500, depending upon 

 the age and size of the fish. With water at 

 fifty degrees Fahrenheit the eggs hatch in about 

 fifty days. But with water at about thirty-four 

 degrees Fahrenheit they will require over 150 days, 

 157 days being the record in one of the New York 

 State hatcheries. Impregnated eggs are amber- 

 colored, and dead eggs are white as chalk, and 

 must be picked out from the good eggs to prevent 

 the spread of disease to the good eggs. Shad eggs 

 are semi-bouyant, non-adhesive, and smaller than 





POSITION OF HANDS IN STRIPPING A SMALL TROUT. 



