OUR RIVER HARVESTS. 283 



intentions of the pisciculturist, and that, instead of 

 making the migrator stay at home, the cross would only 

 send the non-migrator off to sea. 



Moreover, to obtain a hybrid by means of crossing 

 two distinct species of fish is a very different business 

 from getting a mixed breed of varieties belonging to 

 the same species of cattle. And although it is true 

 that even in the wide seas specimens are now and then 

 caught which possess the characteristics of two separate 

 species in such equal proportions that they cannot be 

 referred with certainty to either, yet these exceptional 

 cases prove little but a fact already known ; and though 

 they show that hybrid or mule fishes can be obtained, 

 they fail to demonstrate any advantages to be gained 

 by them. 



We have said nothing as yet with respect to the 

 means by which the eggs are obtained by the piscicul- 

 turist. It is, of course, necessary to be perfectly sure 

 of their genuineness, and the only method by which 

 this question can be decided with absolute certainty is 

 to procure them from the parent fish. 



Nothing is simpler than this process. At the 

 spawning time, just when she is about to deposit her 

 eggs, the female fish is put into a tub with water, and 

 by a little artificial aid the whole of the eggs, or ' hard 

 roe,' are soon laid in the tub. The fish is then released, 

 and suffered to return to her native river. A male fish 

 of the same species is then put into the same vessel, and 

 some of the milt, or ' soft roe,' is deposited in a similar 



