628 OYSTERS, AND ALL ABOUT THEM. 



APPLICATION OF ARTIFICIAL FECUNDATION. 



Is it necessary to insist upon the economy of artificial 

 fecundation, or to bring forward in evidence the advantages 

 offered by it, and to point out the new horizons it opens up 

 to^ostricultural industry ? 



The Portuguese oyster is endowed with a marvellous 

 fecundity.* If all the ova produced annually by the in- 

 numerable subjects to which the Gironde gives protection 

 were hatched, and if, on the other hand, the waters of the 

 river were sufficiently rich to feed them, all portions of the 

 sea would soon be swarmed. The causes of destruction 

 are, however, numerous and powerful, for the collection of 

 spat is always contingent, either owing to the fact of incle- 

 ment temperature, or to the fact that the waves impelled 

 by the winds disperse and destroy those legions of larva 

 which are seen to be hatched. 



Now the methods which we recommend will provide 

 an escape from some of these disturbing causes, and will 

 assure to those who put them in practice a certain harvest 

 in places sheltered from fluctuation of temperature, and 

 where persistent bad weather would not be able to check 

 the regularity of the abundant return. 



* A cubic centimetre of ovary contains: Ova. 



Method of separation - - 2,500,000 



- cups 5,200,000 



Total 7,700,000 



(Average, 3,850,000.) 



The volume of the ovary of an oyster of average size varies from 6 

 to 8 cubic centimetres ; hence an oyster of three or four years old can 

 lay every year about 20 millions of eggs. 



With the ordinary oyster these figures are reduced to twelve or 

 fifteen hundred thousand eggs. 



