84 



water can be circulated. These basins are iutended 

 for the rearing of the salmon alevins, and in this way 

 time may be saved, because the young increase much 

 more rapidly in them than if they were at liberty in a 

 pond. The rearing basins, dug in the soil, should 

 have a depth of at least half a metre to one and one 

 fifth metres, and the banks should be sloping. A 

 width of a metre and a half will be very practicable. 

 They need not be fully stocked with aquatic plants ; a 

 few clumps may be placed in them, which can be 

 arranged in pots buried in the gravelly bottom. The 

 plants which should have the preference are the large- 

 leafed Potamogetons and the Menuphars ; at first they 

 will serve to oxygenate the water and later to furnish 

 shade for the j^oung. 



The breeder may have recourse either to eggs or to 

 alevins ; the latter are always high priced and difficult 

 to transport. It is, therefore, much more practical to 

 procure the eggs, and, from another point of view, it 

 almost alwa3'\s happens that alevins which are pur- 

 chased have been injured and have not been properly 

 fed. It is well to know that in this case the inevitable 

 result will be an arrest of development. They will not 

 become large, no matter how favorable the conditions 

 in which they are placed. 



Preference should be given to eggs, which involves 

 a slight complication, it is true, because it will be 

 necessary to hatch them ; but nothing is easier, and we 

 have today hatching apparatus so simple and practical 

 that hatching is merely a pleasure. 



The price of fertilized eggs of California salmon is 

 about eighteen to twenty francs a thousand. 



After hatching, the fry are transported to the rear- 

 ing basin, and at the end of about fifteen daj's, without 

 waiting for the complete absorption of the yolk sack — 

 I insist especially upon this point — the feeding should 

 be commenced. The food should be suspended daily 



