6l6 OYSTERS, AND ALL ABOUT THEM. 



We commenced by some experiments in the Labora- 

 tory of Embryogeny in the College of France, which, with- 

 out being conclusive, at least indicated to us the course to 

 follow, and the manner in which the experiments should 

 be conducted. In the course of the same year these essays 

 were repeated with great success at Arcachon. Last year 

 we obtained, for the first time, moving larvae. We were 

 greatly surprised at what we observed ; we were quite un- 

 prepared, after an incubation of twelve hours only, for so 

 speedy a manifestation of external life ; our surprise was 

 the greater, inasmuch as at this phase of evolution these 

 larvae show themselves in an aspect in which it is impos- 

 sible to foresee their definitive form. 



On the other hand, we did not discover in what has 

 been described and stated on the subject of the incubation 

 and transformation of the ova of the ostrea edulis any men- 

 tion of this phenomenon of precocious locomotion, which, 

 we believe, had never before been observed.* 



The advanced season of the year in which we were, 

 and the difficulties there were in procuring at Arcachon 

 Portuguese oysters in the state fit for the accomplishment 

 of the generating functions, did not permit us to recom- 

 mence our experiments with favourable result, or to define 

 in what respects they were obscure. 



* At the time when great attention was bestowed in France tojthe 

 artificial fecundation of the ova of fish, a discoveiy just made by the 

 fishermen of the Vosges, Gehin [and Remy, it was Tield out that it 

 would be possible to treat the ova of the ordinary oyster, the only oyster 

 then known to us, in the same manner. But the hermaphrodism of 

 this mollusc having been demonstrated, it became necessary to abandon 

 this hope. At all events artificial fecundation, if in a scientific point of 

 view it had been possible, would never have led to industrial conse- 

 quences, for this reason, that the ova and embryos of the ostrea edulis 

 cannot be developed except in the cavity for incubation. 



