THE NEW ART OF BREEDING FISH. 59 



shallow shelving hanks, with aquatic plants, offering 

 the security which fish seek for depositing their 

 spawn. So too in ponds, the sides of which are 

 evenly dug out hy the pickaxe, the water in which is 

 every where of an equal depth, many of the common- 

 est species either are barren or reproduce vsrith great 

 difficulty. The employment of baskets or tubs in a 

 measure supplies such deficiencies, giving the means 

 artificially of placing the eggs near the surface of 

 the water, exposed to the rays of the sun, and, in 

 fact, in a similar position to that which the instinct 

 of the animal would choose as best suited to their 

 development. 



The absence of running water sometimes prevents 

 reproduction by certain species, though the animals 

 live and prosper, and even spawn. Trout kept in 

 ponds will spawn, the males will fecundate the eggs, 

 but the eggs fall to the bottom and soon perish. The 

 female labors in vain to keep them clean ; with all 

 her care she can only do so for a very few days. 

 They become covered with dirt, and the germ is de- 

 stroyed unless laid in gravel and washed constantly 

 by running water. 



Hatching apparatus overcomes these difficulties. 

 It is only necessary to procure, by artificial means, 

 the eggs and the milt of even such as are unproduc- 

 tive ones in ponds, and by the aid of such apparatus 

 young fish can be obtained to restock them. 



