BULLETIN OF THE UNITED STATES FISH COMMISSION. 213 



24.— ON EXPERIMENTS, BEGIN IN 1SS0, TO PLANT AMERICAN OYS- 

 TERS IN THE WESTERN BALTIC, AND THE ISEFULNESSOE 

 CONTINUING THESE EXPERIMENTS, WITH THE AID OF THE 

 GERMAN FISHERY ASIOCIATION.* 



By K. HIOBIUS. 



At several points on the Baltic Sea, the Greifswald Oie (southeast of 

 the island of Biigen), Warneiniinde, and Kiel, various attempts have 

 been made daring the last forty years to cultivate the European edible 

 oyster ( Ostrea edulis, L.), but all without success. The oysters which 

 had been planted did not propagate, but pined away and finally died. 



Thousands of years ago, when the inhabitants of the Cimbrian penin- 

 sula had no other weapons and implements but those made of stone and 

 bone, oysters must have been frequent in the Little Belt, for at a place 

 on its western coast, near the village of Siiderballig, between Haders- 

 leben and Apenrade, there is a kitchen-midden from the stone age, 

 which, besides many common edible mussels and heart-mussels, con- 

 tains numerous oyster shells. It is evident that the oysters once con- 

 tained in these shells were not brought from a distance, but had been 

 caught in that neighborhood. The circumstance that at one time there 

 were ouster beds in the Little Belt proves that in those times the 

 water of the Western Baltic must have been Salter than it is now. In 

 still earlier times, when the Baltic was not confined within its present 

 limits, but covered a considerable portion of its shore-regions, oysters 

 were found still farther from the two belts, east and south of Kiel, 

 in places which are now 300 to GOO meters above the water-level. The 

 bottom of the Baltic, therefore, has risen in course of time, and so the 

 straits connecting it with the North Sea, the Sound, and the two Belts 

 have become shallower and narrower, in consequence of which the 

 amount of salt water received by the Baltic from the North Sea has 

 decreased, and no longer counterbalances the fresh water which con- 

 tinually pours into it from its tributary rivers. It is certain that the 

 change of the water of the Baltic was a very slow process, which possi- 

 bly is still going on. Our descendants will be able to determine this 

 question, as by the investigations of Dr. H. A. Meyer, and the German 

 commission for the scientific exploration of the German seas, the pres- 

 ent degree of saltness of the water of the Baltic has been accurately 

 ascertained. The oysters of the Siiderballig kitchen-midden are smaller 

 than those of the same age from the oyster beds on the west coast of 

 Schleswig (as the specimens placed on exhibition show). They proba- 



* Vber denim Jahre 1830 begonnenen Yersuch, nordamerikanische Austernin der westltchen 

 Ostsee anzusiedeln und die zweckmassige Fortfilhrung desselben unter etwaiger Beihiilfe des 

 Deutschen Fischerei-Vereins. Translated from the German by Herjiax Jacobsox. 

 From Circular No. 2, 1883, of the Deutsche Fischerie-Verein, Berlin, April 30, 1883. 



