THE NEW ART OF BREEDING FISH. 55 



merit begins to accumulate on them, he removes it 

 with a fine brush. If after being left some time, a 

 sort of coating of vegetable matter should be formed 

 about them, upon the hurdle or basket, he empties 

 them from this dirty one into a clean one, and by 

 means of this easy transfer, which he effects without 

 injury even to the eggs just hatching or the fish just 

 hatched, he maintains the cleanliness necessary to 

 their development. 



But these are not the only reasons for preferring 

 the hurdles just described to the pebbly bottoms re- 

 commended by Jacobi and by the two fishermen of 

 Bresse. There is another no less worthy of considera- 

 tion : it is that after the birth of the salmon or trout, 

 and we speak from having already made the experi- 

 ment, the hurdles will serve as light rafts on which 

 to float, through a channel of communication, the 

 young fry to the pond in which they are to be kept. 

 To do this, it is only necessary to inclose them in a 

 floating frame which the current will carry to their 

 destination. The crowds of people attracted by cu- 

 riosity to the College of France have had the oppor- 

 tunity to see more than 10,000 newly hatched salmon 

 or on the point of being hatched, lying at the same 

 time on the hurdles of a simple apparatus of not 

 more than a square metre of surface. This result, 

 obtained in such restricted space, gives some idea of 

 what may be done on a large scale, and for a regularly 

 organized trade. 



I give here a figure (plate 2, fig. 2) representing 



