REPORT OF COMMISSIONER OF FISH AND FISHERIES. LI 



states tbat it is a fine fish, occupying deep lakes in the nortb of Gennany, 

 and grows to a weight of 1^ pounds. It is never found in German lakes 

 of less depth than 50 feet, and never in running water. It feeds on small 

 crustaceans, worms, and mussels, coming to the surface only at night, 

 especially warm summer nights. In early winter it spawns in shallow 

 water, generally performing this act during the night. Each female 

 bears from 2,000 to 5,000 eggs, which sink to the bottom and adhere to 

 aquatic plants. It is usually caught in large numbers with nets and 

 seines, and brought to the market either fresh or smoked. It is highly 

 esteemed on account of its delicate flavor. 



e. The Grayling (Thijmallus U-icolor.) 



The NorthviUe Station. — Tlie grayling is a famous game fish which 

 seems to be steadily diminishing in number, hence it is necessary that 

 measures be taken for its protection and ^propagation. The work of the 

 past season was largely experimental, as there was no exact knowledge 

 regarding the sx)awning habits of this fish. Many obstacles, also, had 

 to be encountered and overcome, such as deep snow, swift currents, 

 and the great number of logs that were being sent down the Manistee 

 and Au Sable Eivers in Northern Michigan, from which the eggs were 

 obtained ; while the fish that furnished the spawn were caught by hook- 

 and-line fishing. Twenty tliousaud eggs were received, and 5,000 were 

 shipped to the Central Station at Washington, while nearly 12,000 

 were hatched, and tliose that lived were retained at the Northvillo 

 Station for breeding purposes. The period of incubation was found to 

 be from 14 to 20 days, with a water temperature ranging from 50° to 

 02° Fahr. The hatching was successful, about 75 i>er cent of tlie eggs 

 batching out; but fully 90 per cent of the fry died wilhin a couple of 

 weeks, as most of them refused to take food. The few hundred that 

 lived grew rapidly, far exceeding the size of trout of the same age. 



With the experience gained this season, the work of another season 

 would doubtless be more successful. It is suggested, however, that a 

 better way would be to catch the fish during the autumn, when the 

 rivers are free from logs, and to keep them in a suitable place until 

 their spawning time, which seems .to be about the middle of April. 



The Wytheville Station. — On May 1, 1885, 5,000 eggs of the grayling 

 were received at the Wytheville Station. These were batched and ])ro- 

 duced 4,075 young. Heavy mortality occurred after batching, and on 

 May 1, when the young were transferred from the batching troughs to 

 the rearing ponds, only 2,557 remained. These will be retained at the 

 station and the attempt made to rear them in confinement. 



/. The Brook Trout (Salvclinns fontinaUn). 



The Northiullc Station. — The eggs were obtained from the breeding 

 stock at the Xortbville i)onds, more being taken from fish tv\ o and one- 

 half years old than from those of any other age. The hist eggs were 

 taken October 12, and the last January 5. In all 320,850 eggs were 



