42 AMERICAN FISH CULTURE. 



CHAPTER III. 



TROUT BREEDING. 



INCUBATION, AND TKEATMENT OF FRY. 



Hatching apparatus. — French and American plans. — Supply of 

 water for a given nnmber of eggs. Eatchinri -house. — Illustration 

 with explanations. — Filterer. — Troughs. — Nursery. — Management 

 of filterer. — Washing grarel for troughs. — Implements. Taking 

 the spawn. — Action of the female when about to spawn. — Method 

 of catching tlie fish on the spawning-beds. — Indications of the ma- 

 turity of the eggs. ^Manipulation. — Placing the ova in the troughs. 

 — Packing and transportation of eggs. — Manner of taking a large 

 number of eggs for transportation from a trough. — How to examine 

 them. — Illustration with explanations of the appearance of ova at 

 different stages during incubation . — Table showing progress of incu- 

 bation with water at different degrees of temperature. — Hatching 

 out and progress in growth and activity of fry. Treatment of fry. 

 — Their food, and manner of feeding them. — Their disposition to 

 escape. — Transferring them to the nurseries. — Their admission into 

 the first pond. — Transportation of fry. 



Hatching Apparatus. — Since the early experliueuts of 

 Remy, a great many improvements liave been made in 

 hatching fish spawn. At Huningue, trays or troughs of 

 earthenware about twenty-five inches long, five inches wide, 

 and four inches deep, are used. The eggs are placed on 

 a grille, made by arranging small parallel cross-bars in a 

 wooden frame, which rests on projections on each side of 

 the tray, a little below the surface of the water. The bars 



