118 FISH FARMING : 



trays for the purpose of incubation. The milt of one male 

 Fario is generally sufficient to impregnate 10,000 eggs cf a 

 female of the same species ; but in the case of Irideus the milt 

 of one male fish should be used over not more than 5,000 eggs 

 One other point. When spawning Irideus it will be found 

 that more moisture accompanies the eggs of the female fish 

 and this should be permitted, so that less water is necessary 

 in the spawning-dish after impregnation. 



It is pretty generally accepted by all fish-culturists that the 

 periods at which the greatest loss occurs in connection with 

 the reproduction cf the SaJmonidae in a natural manner are : 

 First, at spawning time, through imperfect impregnation 

 (only a proportion of the eggs becoming impregnated), and 

 through the ravages of the numerous enemies to fish eggs, in- 

 cluding, cf course, salmon and trout themselves ; and, second, 

 that period immediately, succeeding the absorption of the um- 

 bilical sac. The latter is dealt with in another place (see 

 rearing young fry), and the former is best remedied by arti- 

 ficially spawning the fish, as I have described above, and hatch- 

 ing them in ai proper hatching house and in suitable trays, 

 after the manner I next propose to tell you. 



