BULLETIN OF THE UNITED STATES FISH COMMISSION. 391 



stripping movement is executed which causes the eggs to flow rapidly into the 



'pan, which should be elean and without water. 'When all the spawn is taken 



it will be shown by the blood appearing among the eggs. Take two or three 



females in this manner, then pick out a male, handle him in the same way, 



forcing out two or three jets of milt upon the eggs, swaying the pan gently to 



and fro ; a little icater should be added from time to time until the eggs rise, 



which will be in the course of half an hour; the scales and blood must be 



rinsed oft'. After they are impregnated, the eggs will be seen to have 



increased in size; when they have risen they can either be put on the trays 



or else kept in the pan. Eggs taken at different times must be kept in 



separate vessels. 



To put the eggs on the trays. — Wet the cotton cloth, spread it out 

 smoothly over the tray, and pour the eggs carefully upon it, not more 

 than two layers deep ; by keeping the cloth moistened from time to 

 time, eggs can be kept in good condition for twenty-four hours. 



When eggs are kept in the pans they should be filled with water, 

 which ought to be changed at least once every hour ; the water should 

 be poured in on the side of the pan in order not to injure the eggs. 



In stripping fish many scales will come off and fall into the pan un- 

 less great care is taken. The scales should be gathered and thrown 

 away by a quick movement of the hand, otherwise the eggs will become 

 attached to them. 



All eggs should be as clean as possible, and free from dirt, blood, or 

 scales ; they should be kept free from exposure or violent shbcks. 



Bad eggs will float on top ; they are white, being called water-blown; 

 they should be gathered aud thrown away. 



Good eggs will be clear and like crystal in appearance ; when they 

 have risen they will feel like shot to the hand if they are gently stirred. 



Sometimes eggs assume this appearance when they are not properly 

 impregnated. In such cases they are worthless and will not hatch. It 

 is, therefore, impracticable to determine with certainty that eggs are 

 properly impregnated until development has advanced somewhat, and 

 fche formation of the fish is discernible in the egg. 



The utmost pains must be taken to keep the fish from slipping out of 

 the hands, or they will fall into the pan, throw a large number of the 

 eggs out, and damage the rest. 



