REPORT OF COMMISSIONER OF FISH AND FISHERIES LXV 



Fry were observed within three or four days, and by the end of the 

 month the fish had nearly finished spawning. The temperature during 

 this period varied greatly, but the results were not injurious, appar- 

 ently, as only four nests appeared to be affected with fungus. 



The following shows the temperature of water on the spawning-beds 

 from April 20 to 30, inclusive, taken at 7 a. m. and 4 p. m : 



As soon as the schools of young bass dispersed they were allowed to 

 pass from the spawning beds to the main ponds, and the adults were 

 again transferred to the stock ponds. The young fish were fed, as 

 usual, on carp and tench reared for the purpose, from 400,000 to 500,000 

 carp a few days old aud a large number of tench being placed in the 

 north and south ponds during the season. At the close of the fiscal 

 year the indications were that the crop of bass would be large, but it 

 was impossible to form any definite idea of the number in the ponds on 

 account of the dense growth of algae. 



In October the shad placed in the west pond during the previous 

 spring were liberated in the Potomac Eiver as usual.. The number 

 released was estimated at about 3,000,000. In May, 1898, another con- 

 signment of 3,537,000 were put in the same pond to be reared. 



Some attention was paid this season to the propagation of frogs. A 

 number of adults were placed in Pond 19 during the spring, and at the 

 close of the year there were 4,000 young ones. Their hind legs had 

 developed, but the fore legs were not yet visible. They were taking 

 food freely. The old frogs live on bumble-bees, dragon-liies, ordinary 

 flies, beetles, and moths that come within their reach over the grass 

 borders. A number of the tadpoles were transferred to the aquarium 

 in Central Station, aud it was found that they would take cornmeal 

 readily. It is intended to continue these experiments in the future in 

 the hope that some useful information may be gained with refereuce to 

 the culture of frogs iu ponds. 



The pond which had been stocked with fresh-water shrimps from 

 North Carolina was examined during the fall of 1897 and 5,400 were 

 found. Twenty-five of them were removed to a tank in the greenhouse 

 aud were carried through the winter in excellent condition. No trace 

 of the others could be found in the spring, and it is thought that they 

 were killed by the severe frosts. 



Notwithstanding the efforts during the past two years to eradicate 

 injurious plauts and insects from the ponds by drawing off the water 

 F. r. 98 v 



