356 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



the piles of the wharves, shells along the beach and on the beds, and 

 oysters, without finding any young of this year's growth, he thinks it 

 possible that the failure of the experiment was due to conditions isnd 

 iiitlueuces beyond our control rather than to any inherent defect in 

 the apparatus. Coupling the absence of any "set" about Hampton 

 Eoads, with the difliciilty we experienced all snmmcr in securing the 

 fertilization of the eggs, it is possible that Dr. JJrooks is correct in his 

 opinion. Certainly the oysters did not die for want of food, as when 

 from four to five weeks old they were in a healthy condition, with 

 fall stomachs and receiving an abundant sup})]y of water. 



I much regret that we should again have failed both in producing 

 young oysters and in gaining additional information of biological inter- 

 est. We have, however, discovered a niethod by which food can be sup- 

 plied the oysters in unlimited quantities, which is a considerable ad- 

 vance, and may lead to the solution of the problem in the future. 



At my request Dr. Brooks has stored the troughs with the apparatus 

 and furniture of the Johns Hopkins laboratory at Hampton, so that 

 they may be readily available for next summer should you consider it 

 advisable to continue experimenting. 



North Dunbarton, N. H., September 13, 1883. 



ir§ — THE OYSTER AS A P©I»Uff>AK ARTICLE OF FOO0 IIV IVORTH 



AMEKBCA.* 



By CARL RUI^IPFF, 



Memher of the German Parliament, 

 [Read at the meeting of the Germau Fishery Association, March 8, 1884.] 



Accidentally I learned last year, partly from the president of the as- 

 sociation and partly from the jjublished reports of the association, that 

 after all attemj^ts to transplant the Kortli Sea oysters to the coasts of 

 the Baltic had failed, the same failure had to be chronicled as regards 

 the efforts to transplant to the Baltic the North American oyster {Ostrea 

 rirginica). The reasons why none of these oysters have propagated in 

 the Baltic have been thoroughly investigated by Professor Mobius, of 

 Kiel ; and it has been ascertained that the failure was owing to two 

 causes, viz., the smaller degree of saltuess of the water (in the North Sea 

 and on the coasts of the United States, 2^ to 3 per cent ; in the Baltic 

 only ].3 to 1.5 per cent), and the colder temperature generally prevail- 

 ing during a considerable part of the winter. 



Further investigations of the German Fishery Association directed 

 attention to more northerlj^ districts of the American continent ; and 



* TJe'ber die Bedeiitung der Avstern filr VolKserncihritiiff in Nord-Amerila. From Circu- 

 lar No. 3, lySt, of the Germau Fishery Associatiod, Berlin, April 4, 1884. Translated 

 from the German by Herman Jacobson. 



