BULLETIN OF THE UNITED STATES FISH COMMISSION. 281 



44.-REARIIV« OYSTERS FROJU ARTIFICIALLY FERTILIZED E«C5S, 

 TOGETHER WITH NOTES OUT PONDCI'LTIRE, Ac. 



By JOHN A. RYDER. 



The desirability of testing tbe breeding of oysters in ponds in the 

 United States, as practiced for many years past in France, has long been 

 a desideratum. 



In order to test the feasibility of such a method on a scale large 

 enough to give us practical results, an arrangement to carry out such a 

 scheme was finally effected with the Eastern Shore Oyster Company in 

 June of the present year. The beds near where the work was under- 

 taken are owned by Messrs. Pierce & Shepard, who afforded the writer 

 every opportunity to carry on his investigations, and also aided him 

 very materially in the work of experiment. A pond was excavated in 

 the salt marsh on the shore of Chincoteague Bay, on a farm situated at a 

 distance of about 2 miles from the village of Stockton, Worcester County , 

 Maryland. This pond covered an area of about 50 square yards, and 

 was connected with the bay by a trench or canal about 10 feet in length, 

 2 feet in width, and 3£ feet in depth, which last was the same as that of 

 the pond itself. 



The water which supplies this pond was filtered through a permeable, 

 porous gate, or diaphragm, which was placed in the trench connecting 

 the pond with the bay, and no water was allowed to enter the pond 

 which had not been first filtered through this diaphragm. 



The diaphragm itself was constructed of boards perforated with 

 auger holes, and lined on the inside with gunny-cloth or sacking; and 

 the space between the perforated boards filled with sharp, clean sand. 

 The space between the boards was about 2 inches ; through this the tide 

 ebbed and flowed, giving a rise and fall of from 4 to 6 inches during the 

 interval between successive tides. 



This apparatus, if it may be called such, constituted the receptacle 

 into which the artificially fertilized eggs of a number of oysters were 

 introduced every two or three days. 



It was supposed, when tbe experiment was commenced, that some 

 difficulty would be experienced with a rise of temperature in the pond 

 in excess of that found in the bay, because the water was kept con- 

 fined and still, and constantly exposed to the direct raytj of the mid-day 

 sun. But to our surprise and gratification it was learned that the tem- 

 perature in the pond and in the bay was precisely the same at every 

 observation which was made in order to test this question. 



Another question also arose in our minds as to whether it might not 

 be that the water in the pond might become less salt than that in the 

 open bay; in other words, that its specific gravity would be less than 

 that of the water iu the bay, owing to leeching from the banks of the 

 pond in addition to that precipitated during rains. 



