L REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



able. These were purchased at a rate of 3 cents per pound. In pre- 

 paring fish as food the scales and gills should be carefully removed. 



With the view to enlarging the output of bass, spawning-ponds 

 were constructed along the south banks of the north and south ponds 

 during the winter, and the stock was increased by the transfer of 

 several hundred large-mouth breeders from Quiucy and small-mouth 

 breeders from Lake Erie. On the loth of April 20 adults were placed 

 in each of the partitions of the north pond and the same number of 

 small-mouth bass were placed in the various partitions of the south 

 pond. Spawners were also placed in Pond No. 6 and in a number of the 

 small i)onds on the terrace in front of the cottage. 



As good results had been attained at Wytheville Station the pre- 

 vious year by the use of artificial nests, all of the ponds were provided 

 with them, in addition to piles of gravel. The nests used were of two 

 forms, one being simi)ly a cement plate 20 inches in diameter, covered 

 with coarse gravel; the other, the Seagle nest, described in the Eeport 

 for 189G, page 48. The fisli commenced spawning on April 18, and it 

 was noticed that they deposited their eggs on the artificial nests quite 

 as readily as on the natural nests of gravel. 



The temi^erature of the water at the opening of the spawning season 

 was 45'^. Fungus developed after a few days on the first eggs deposited 

 in partitions 1 and 2 of the north pond and Pond No. 6, but the others 

 did well, and on April 26 young fish were seen in both the north and 

 south ponds. 



Owing to the faet that the ponds were not dried during the winter, 

 there was an immense growth of algoe, which not only interfered mate- 

 rially with tlie removal of the fry, but i)revented close observation of 

 their movements. As au examination of the jjonds showed them to 

 be abundantly stocked with microscopic food, artificial feeding was not 

 commenced until the bass were about two weeks old. 



During the month of May there was every reason to expect a large 

 crop of both species, but late in June a small bug belonging to the 

 family of Notoneciidw made its appearance and destroyed large numbers 

 of the young fish. 



An insect which belongs to the Bytiscidcv family appeared later and 

 caused even greater danmge. It attacked the young bass in large 

 numbers, killing and eating in a few minutes a fish 1^ inches long, 

 nothing remaining but the skeleton. Tliougb little is known of the 

 natural history of this insect, it has heretofore been thought that its 

 food consisted solely of dead flesh. The pests fly over into the ponds 

 at night from the river, and the only way to prevent their ravages is 

 to cover the ponds with very fine meshed netting. 



At the close of the year, owing to heavy losses caused by the insects 

 referred to, very few of the young fish remained in the small ponds. 



Crappie. — As the demand for this species is constantly increasing, a 

 supply of adults was brought to the station from Quincy in the fall, and 

 early in April 23 of them were placed in Pond No. 5 and the remainder 



