SALMON AND TROUT CULTURE. 451 



impregnated by coming in contact with ripe milt, the fish, both 

 male and female, being taken at random, we are compelled 

 to admit, however unwillingly, that the origin of fish life, 

 in artificial impregnation at least, is wholly a mechanical 

 affair.' 



Unless, however, a very large percentage of fertilised ova 

 is shown, and unless these are taken from strong, healthy 

 parent fish, the pisciculturist's labours are incessant and irksome, 

 as he will have to be constantly removing * blind ' or unimpreg- 

 nated eggs, and weakly * fry ; ' whereas, if his breeders are 

 healthy, and his eggs properly taken, he may reasonably reckon 

 on a large proportion of strong, healthy fry, which will in due 

 course, and with proper treatment, develope into valuable 

 yearling fish. 



The discovery of the 'dry method' of impregnation, by 

 M. Vrasski, a Russian, about the year 1856, is of the greatest 

 practical importance. It was not, however, until some years 

 after, that it became generally known in America, and still later 

 in this country. 



Stone (p. 105) says : 'No one hereafter, who has heard of 

 the new method, will ever take the eggs of any cold water fish 

 by the old method. Seth Green reached the same results 

 nearly ten years before, by using a very small amount of water 

 in the impregnating pan ; ' and Frank Buckland (' Familiar 

 History of British Fishes,' p. 303) found that by placing 

 milt in water first, and then adding the eggs, he obtained 

 better results. In this case, I presume that the eggs were 

 added within a few seconds after the milt had been placed in 

 water. 



By the 'dry method,' nearly one hundred per cent, of the 

 ova taken can be fertilised ; whilst by the old plan of placing 

 both the ova and milt in water, the average scarcely ever 

 reached higher than fifty or sixty per cent. There was always 

 risk, by the old method, that the absorbing power of the egg 

 had ceased before the milt was added, or that the vitality of 

 the milt had disappeared when several minutes elapsed before 



