fish spawn and in which the ova hatches ; must know 

 also the period of the self-sustenance of the infantile 

 hatching, its natural food after the expiration of this 

 period, its nature and habits throughout its entire 

 development to full maturity. 



A practical illustration of the importance of 

 these considerations is furnished in the raising of 

 each and every kind of fish known to pisciculture. 

 An example in point is cited from the writer's own 

 experience in the treatment of white-fish, as pub- 

 lished in the Forest and Stream, over his own sig- 

 nature, bearing date, Clarkston, June 29, 1874, as fol- 

 lows: "About November 15th, 1869, through the kind 

 assistance of Mr. Seth Green I placed 50,000 white- 

 fish ova in my hatching troughs, in spring-water, at 

 a temperature of 47 Fahrenheit, at this place where 

 I was then hatching brook trout successfully. I 

 soon discovered that these eggs were entirely dif- 

 ferent in their nature from those of the brook trout, 

 for within two weeks' time, nine-tenths of them had 

 turned white and were worthless, and I was about 

 to abandon them in despair. 



At this critical time, Mr. Green came to my relief, 

 and after a careful investigation, we found a 

 small portion had indications of vitality in them and 

 he advised me to carefully remove all the good 

 eggs, and by this means I succeeded in hatching 

 about 2,000 in good condition Jan. 15th. 



These fish were entirely different from the young 

 trout when first hatched out, as the moment they 

 emerged from their shell they darted off and ex- 

 hibited a rapid motion in the water, while the latter 



