108 THE NEW ART OF BREEDING TISH. 



tation in such case is allowable only when an adequate 

 trial renders success doubtful ; but here experience 

 has already furnished such positive results, that there 

 cannot be the least doubt of the success of the ope- 

 ration. 



Time presses, sir ; and there are only three 

 months before we come to the breeding season of 

 salmon and trout. If at that time the apparatus is 

 wanting, we lose the most interesting part of the re- 

 quired work. I trust, then, you will give me the 

 order for a credit of 30,000 francs, immediately open 

 to the engineers of the Rhone and Rhine Canal, and 

 I shall be happy to offer you my assistance for the 

 organization of an establishment so founded, and to 

 take my part in the responsibility of an enterprise 

 which will be a signal honor to the administration. 



I cannot terminate this Report, sir, without 

 speaking to you of the propagation of fresh-water 

 shell-fish ; experiments which I have made under 

 the hope of applying them to salt-water shell-fish, 

 whose multiplication would not be difficult to secure. 

 Here, then, is an account of these experiments : — 

 I placed, at the College of France, in a basin, 

 hke that wherein my young salmon live,- fed by a 

 rivulet, a certain number of female craw-fish, all car- 

 rying under the tail their eggs. At the end of twen- 

 ty-five days, all these eggs were hatched, and the 

 basin was usurped by a myriad of young craw-fish, 

 which grew perceptibly. This result proves how 

 easy it is to restock all running streams which an 



