258 PROPAGATION OF FISH. 



troughs ; it should be about six inches in diameter, in the 

 shape of the letter D, with the handle on the middle of the 

 bend. It is very easily made by bending a wire in the 

 desired shape, and twisting the two ends together for a 

 handle. Thin gauze of some kind, like bobinet, should 

 be spread over the wire so tightly that the middle of the 

 net shall hang only a half inch below the level. An iron 

 spoon, w'ell tinned or silvered, is used to remove the eggs. 

 Some six-quart tin milk-pans will be necessary, for a 

 variety of purposes. Eggs may be counted most easily by 

 measuring them. For this purpose take any small glass, 

 such as a very small tumbler, for instance, count out five 

 hundred or a thousand eggs, and with a file make a mark 

 upon the glass as high as they reach, and the measure is 

 always ready to your hand. 



A watering pot with a fine rose spout is used to wash 

 sediment from the eggs on the sieves, and a broom of twigs 

 is used to brush the screens of wire. 



One of the most curious and interesting results of fish- 

 culture has been the production of hybrids, some of which 

 were reproductive and have thus created new species. 

 Strange as it may seem, these experiments have rarely 

 been wholly abortive ; no matter how dissimilar the fam- 

 ilies, the eggs have been impregnated often to a large per- 

 centage, and have hatched. The following varieties have 

 been crossed : 



FEMALE:- MALE. 



Salmon-trout with White-fish. 



" " Brook-trout. 



Brook-trout Fresh- water Herring. 



" " California Salmon. 



" " " Mountain-trout. 



Shad Striped Bass. 



" Herring. 



