552 REPOET OF COMMISSIONER OF FISH AND FISHERIES, 



was used. I examiued tiiese eggs several times during this process, 

 and found a fine, clammy substance accumulating on them. They were 

 gradually dying, and I do not think any were hatched. These eggs 

 were taken from our hatching-boxes, and were in perfect condition, as 

 they were so far advanced in development that the embryo fish could be 

 plainly seen with the naked eye. For these reasons I am forced to the 

 conclusion that there is more suitable water for hatching this species of 

 fish-eggs than the Detroit River. 



" I wish, however, to have it distinctly understood that salmon, sal- 

 mon-trout, and brook-trout should be incubated in pure spring-water, 

 as they will liatch the latter part of January or early in February. They 

 have an umbilical sack from which they derive their subsistence, and 

 which takes about fifty days to absorb. They do not require food dur- 

 ing this period. After this, by feeding them a few days, they will do to 

 turn loose in water adapted to them, where they will find their own 

 food. For these reasons it would be very desirable if your commission 

 could find a location where both spring and lake water could be sup- 

 plied in sufficient quantities to insure the success of breeding both kinds. 

 " Most respectfully and truly yours, 



"N. W. CLARKE. 



" Clarliston, September 13, 1873." 



In conclusion, the adv\intages afforded American fish-culture from the 

 cultivation of the white-fish as they have just been enumerated: These 

 are; (1) more careful and perfect methods, resulting from the experiencein 

 the culture of the most delicate and difficult species whose propagation 

 has been attempted by culturists ; (2) the perfection of three forms of 

 apparatus for hatching fish eggs, embodying the important improve- 

 ments of facility in handling the eggs and removing sediment and con. 

 ferv.TB, and greatly economizing space ; (3) the contrivance of a superior 

 case for the carriage of eggs; and, besides, a possibly successful, en- 

 tirely new method in the hatching of eggs and the discussion of and 

 practical tests of conditions of water suitable to the eggs of a species 

 that we are not (at any rate thus far) able to supply with food. 



TJie Otsego hass. — Another species (?) of white-fish (Co re^/ojiws otsego) has 

 been successfully propagated at Cooperstown, N. Y. A large quantity 

 of eggs were impregnated in the autumn of 1871, and in the following 

 March several thousands of young fishes were set free in the lake. In 

 1873 a larger number were released, and a quantity of eggs put into the 

 hatching-troughs. 



The salmontront—ln the fall of 1857 and 1858 a large number of eggs 

 of salmon-trout were obtained for Saltonstall Lake in Connecticut from 

 Lake Ontario. The enterprise is referred to more fully on page 534. 



A minor experiment in hatching salmon-trout, or Mackinaw trout, 

 iSalmo namaycus]i,)yvas made by Mr. Samuel Wilmot, of Newcastle, Can- 

 ada, in 1SG8. He also obtained a hybrid between a male Sahno salar 

 and a female S. namaycush. The next published records we have of ex" 



