2 



TJ. S. BUEEAU OF FISHERIES. 



An examination of the following table will show that after 1900 

 " sets " in this region became generally light or scattering until 1911, 

 when an excellent " set " was obtained, and that thereafter there 

 was only one important '' set " — that of 1914. Such was the situ- 

 ation in the Connecticut oyster-gTowing region when the bureau's 

 investigations were begun in the spring of 1917. This state of 

 aflfairs, which has continued up to the present time with slight modi- 

 fications, was, of course, particularly menacing to an industry so 

 largely one of seed production. AAliat was the explanation of this 

 lack of set. and what could be done to restore it ? Intelligently to 

 answer either of these questions, even in part, there is required an 

 understanding of the development or life history of the oyster, par- 

 ticularly the early life history, and a due appreciation of the factors, 

 local and general, that affect its development and distribution. 



Table showing the extent of oyster sets in Connecticut iraters from 1885 to 1923, 



inclusive.^ 



' Compiled chiefly from reports of various oj^ter houses, and since 1917 from personal observations, 

 s It is reported that there was a good set in this year, but that it was destroyed by storms. 



f: 



In its final stage the oyster is a sessile bivalve, fixed to one spot and 

 taking from the water only such minute food as comes within the 

 reach of the current produced by means of the wave action of its 

 infinitely numerous cilia. In the younger stages its life is quite 

 different. 



As Brooks - discovered many years ago, the sexes of the oysters 

 of the Atlantic coast of the United States {Osh^ea elongata Solan- 

 der) are contained in different individuals — not combined in one, 

 as is the case with the European oyster, Ostrea ediiUs. The female 

 oyster produces many millions of minute eggs or female reproductive 

 cells; the male, countless millions of still more minute actively swim- 

 ming sperms. With the warming of the water in the sjDring the 

 oyster feeds more and more actively, and the development of the 

 sexual products takes place. Finally, when these are matured, eggs 

 and sperms are cast into the water under the influence of an increase 

 in water temperature. If eggs and sperms are cast at the same time 

 from oysters near one another, the sperms find the eggs and develop- 

 ment of the oyster begins. If neighboring oysters do not spawn at 

 the same time, union of male and female cells fails to occur, and 

 whatever spawn is cast is wasted. 



~ Brooks, W. K., " Development of the American, oyster." Report of the Commissioners 

 of Fisheries of Maryland, January, 1880 (for 1879/, pp. 35-37. Annapolis. 



