THE NEW ART OF BREEDING FISH. 83 



multiplying their numbers, long well known to phy- 

 siologists, and often experimentally employed in their 

 cabinets, namely, that of artificially fecundating the 

 eggs. We know by the labora of Spallanzani, and 

 by the experimental researches with which you, your- 

 self, Mr. Minister, and your ancient colleague, Prevost 

 (of Geneva), twenty five years since enriched science, 

 that all fecundation is the result of the action exer- 

 cised upon the egg at its state of maturity by the 

 living spermatozoa with which the semen or milt is 

 vhai-ged ; that this action takes place through the 

 direct contact of these two reproductive elements, 

 and that the physiological puissance of these same 

 agents may be preserved during a longer or shorter 

 period after they have been taken from the living 

 bodies which have given them existence. 



With a great number of inferior animals the par 

 rent's part in the work of reproduction, consists only 

 in the formation and emission of these two generic 

 elements ; the egg is not impregnated till, after be- 

 ing spawned, it meets the spermatozoa, the contact 

 with which, necessary to endow it with life, only 

 takes place by the concurrence of exterior causes, in- 

 dependent of the action of the parents, for example, 

 by the course of the current in which the milt is de- 

 posited. The experimentalist can, therefore, det;pr- 

 mine at will this physiological phenomenon, by 

 mechanically mixing the eggs and milt of these apir 

 mals, and the same results will be obtained, by this, 

 process as by the natural one. 



