J. PISCICULTURE AND THE FISHERIES. 419 



water, excluded permanently from access to the sea, and 

 quotes the impressions of the Marquis of Breadalbane and 

 others that the salmon in Loch Tay, a well-known fresh-water 

 lake of Scotland, never leave it except when they ascend its 

 tributaries to spawn, and that they return to the lake, and 

 there become clean without going down through the outlet 

 of the Tay to the sea. This is a decided encouragement to 

 those who propose to try the experiment of introducing the 

 salmon into the great North American lakes, as it is well 

 known that in these bodies of water are to be found the tem- 

 perature and kind of food required by salmon, and for which, 

 in part, they probably visit the ocean. 



It is an interesting fact, substantiated within a few years, 

 that a small crustacean of the genus Mysis, which is believed 

 to constitute in great part the food of the salmon in the 

 ocean, occurs also in these lakes in immense numbers at cer- 

 tain depths, and that consequently their necessities in this 

 respect can be met without leaving the fresh water. The 

 writer in The Field also remarks that the British sea-trout 

 (Salmo trutta) will thrive and breed perfectly well in fresh 

 water, and advises that it be used in stocking ponds and 

 lakes rather than the common trout, as being a much better 

 fish for the table, and remaining much longer in good condi- 

 tion. 19 A, August 3, 1872, 124. 



PROFITABLE RESULT OF SALMON -PLANTING IN GERMANY. 



The practical result of the introduction of salmon into suit- 

 able rivers is well shown by the report, lately published, of 

 experiments made in the German river Weser, by Schieber 

 (the Inspector of Fisheries at Hameln) about 120 miles from 

 where the river empties into the German Ocean. In April, 

 1858, 80,000 eggs, ten weeks old, were deposited; in 1859, 

 31,000 ; and in 1860, 29,000. As the result, at the expiration 

 of four years, the number of salmon taken at Hameln had in- 

 creased fivefold, and in 1863 eightfold. Up to 1862 the catch 

 at Hameln had amounted to from 400 to 500 fish annually, 

 while in 1862, 2600 were taken; in 1863,4000; inlS64,5000. 



In 1862 and 1863 no young were introduced, and conse- 

 quently, in 1865, only 1500 fish were taken; in 1866,1100; 

 and in 1867, 900. Mr. Schieber concludes, from his investiga- 

 tions, that the period of four years elapses between the hatch- 



