214 FISH CULTURE 



then sieved through, wire trays of very fine 

 mesh, care being taken that the work is done in 

 the gloom of the hatching-honse. The screen is 

 held in a tub of water close to the surface, and 

 as the eggs are rubbed through they fall to the 

 bottom. The sieving is repeated two or three 

 times until the eggs are entirely free from each 

 other and do not adhere. They are then trans- 

 ferred to hatching-jars. 



At Cold Spring Harbor, New York, where the 

 bulk of this work is done, the McDonald auto- 

 matic jar and the old table system is used; but 

 the eggs can be hatched in the open Downing 

 improved, or in the Meehan jar, quite as effec- 

 tually. It has been found that excessive light, 

 or even as much light as is ordinarily admitted 

 in a hatching-house for pike-perch, shad, and 

 most fishes, is fatal to smelt eggs; therefore 

 after the jars have been put in place, and the 

 water turned on, a black curtain should be hung 

 on each side of the battery, so that the eggs 

 wUl be in complete darkness. Although the 

 eggs are very adhesive, and frequently "ball" 

 in the same manner as pike-perch eggs, they are 

 very easily handled. It is only necessary to 



