ii4 Our Food Mollusks 



country, and many attempts were made to repeat it here. 

 The first of these was made in 1883 by Professor John 

 A. Ryder, in a small pond on the shore of the Chesapeake. 

 The excavation was a little more than twenty feet square, 

 and about three and a half feet deep. Water from the 

 bay was led into it by a ditch. In order to exclude young 

 swimming oysters from the entering water, it was caused 

 to flow through a sand diaphragm constructed in the 

 ditch. After stakes, suspending shell collectors, had been 

 placed in the bottom, artificially fertilized oyster eggs 

 were poured into the pond from time to time. About 

 seven weeks after the beginning of the experiment, the 

 collectors were found to bear young oysters varying 

 from a fourth to three- fourths of an inch in diameter; 

 but the set appears to have been so meager as to have 

 offered no encouragement to oyster culture. In sum- 

 marizing his results, Professor Ryder concluded, " The 

 writer does not think that the rearing of oysters from 

 artificially impregnated eggs will ever be a profitable 

 business." 



Similar results were obtained from ponds constructed 

 on the shores of Long Island Sound and elsewhere, but 

 none were really successful, and some were entire failures. 

 The accounts of most of the experiments are too vague 

 and imperfect to be valuable. For example, a " good 

 set " was obtained in a Long Island pond two hundred 

 and eighty feet long and one hundred feet wide, and con- 

 taining from two to six feet of water. But we do not 

 know the observer's idea of a good set. From the ac- 

 count one must assume that water was led directly into 

 the pond from the harbor near at hand, and that no at- 

 tempt was made to exclude swimming oysters from it. 

 Some years later that harbor was literally paved with 



