34 THE NEW AKT OF BREEDING FISH. 



but a grated opening, similar to the rest, six inches 

 square, may be left to give light to the young fish ; 

 this however is not absolutely necessary. 



" A suitable place should then be chosen for the 

 box, near a rivulet, or, what is still better, near a pond 

 supplied with running water, from which may be 

 drawn by a little canal a stream, say an ihch thick, 

 which should be made to pass continually through the 

 gratings and through the box. 



" Lastly, the bottom of the box to the thickness 

 of an inch should be covered with sand or gravel, and 

 over this should be spread a bed of stones of the size 

 of nuts or acorns. 



" Thus will be made a little artificial brook run- 

 ning over a gravelly bottom." * 



It is then in this artificial brook, where, I repeat, 

 are found so cleverly united all the conditions sought 

 by the female in a state of nature, that the author 

 of the memoir published by the Count de Groldstein, 

 deposits the eggs fecundated by the artificial process, 

 the discovery of which belongs to him. 



" The eggs thus fecundated are spread," he says, 

 " in one of the boxes so placed, and the water of 

 the little rivulet passes over them, care being taken 

 that it does not run with such rapidity as to displace 

 and carry away with it the eggs, for it is necessary they 

 should remain undisturbed between the pebbles. "f 



When he had thus scattered the fecundated egga 



* Duhamel, op. cit., 2d part, p. 334. 

 f Duhamel, op. cit., 2d part, p. 336. 



