122 AMERICAN FISH CULTURE. 



within a few years. A channel connects the ponds with 

 the river, for the passage of the smolts to sea, a perforated 

 sluice heing opened at the proper time for their egress. 

 The smolts can be detained by a sluice near the river when 

 any of them are to be marked. 



The time of incubation here, is from a hundred to a 

 hundred and thirty days. The fry remain in the hatching- 

 boxes five or six weeks, and then find their way to the first 

 pond, where they remain for a year, and are then turned 

 into the second pond, that the succeeding brood of fry may 

 occupy the first. From the second pond, when they become 

 smolts, they are turned into the river through the channel 

 referred to above. Marking them is done generally by 

 clipping or notching the adipose dorsal fin. The fry are 

 fed regularly on boiled liver grated fine, rising to the sur- 

 face in thousands when it is thrown in. 



The spawning fish are taken at Almond Mouth, about 

 three miles distant, with the common draught net,' and 

 manipulated there. When a rise in the river sufficient to 

 interfere Avith taking the fish is apprehended, they can be 

 taken some days before they are fully mature, and kept in 

 the mill-lade mentioned at the beginning of this article; 

 being kept within bounds by two rows of iron bars set 

 across the lade, one row about a hundred yards from the 

 other. Mr. Peter Marshall, the superintendent of the works, 

 is the operator. Holding the femdle firmly or having her 

 held, he brings his hand with a gentle pressure down the 

 belly, when the ova are ejected into a pail of river water; 

 manipulating the male in the same way, he extrudes the milt 



