54 



obtain, if possible, satisfactory information in regard to the sex of the oyster, the method of prop- 

 agation, the number of embryos spawned, and the habits of the animal during the early stages of 

 life; or, in general terms, it was intended to make the study of the embryology of the oyster part 

 of the work of the party. 



It was proposed to continue this branch of the inquiry throughout the year, and to make, by 

 means of self-registering thermometers and careful series of density observations and chemical 

 analyses, an exhaustive study of the character and changes of character of the water surrounding 

 the animals on the beds. 



Another division of the party was to uudertake the collection of statistics, and was to visit 

 and inspect all the dredging vessels and packing houses, that some value might be assigned the 

 dredging factor, to which most of the evils affecting the beds appeared to be due. 



The smallness of the annual appropriation made it impossible to carry out the original plan, 

 which was accordingly modified; and the want of funds, which reduced the size of the party and 

 scope of the work, also prevented our getting into the field before July 1. Thus the opportunity 

 for studying the embryology of the oyster and many other matters of interest relating to the 

 reproductive processes was unavoidably lost. It was decided, however, to attempt the execution 

 of the original design so far as was possible with the diminished force and time at our disposal, 

 but upon our arrival at Crisfield, Md., it was found necessary to again modify and change our plan, 

 or else duplicate an investigation that had already been undertaken and ably executed. 



Members of the Johns Hopkins Zoological Laboratory had been established at Crisfield for 

 some months prior to my arrival, and Dr. W. K. Brooks had begun the study of the embryology 

 of the oyster, had made experiments in impregnating the ova with the spermatozoa, and had suc- 

 ceeded to some extent in raising the oyster from the egg. The study of the embryolgy of the 

 oyster was thus not only undertaken but concluded, so far as was possible, during that season. 

 The results were alike surprising, interesting, and valuable, and, having been accomplished by so 

 able a worker, did not need any confirmation at our hands, and as it was his intention to continue 

 his experiments in the future and trace the development of the oyster up to the point of attach- 

 ment, I wrote to the Superintendent proposing a new scheme for the season, which met with his 

 approval, and which contemplated the abandonment of all investigation of the embryological life 

 of the oyster. 



The work of the party during this season was, properly, the collection of such information as 

 would conduce to correct answers to the following questions: 



1st. Were the oyster beds improving or deteriorating? 



2d. What were the causes for such improvement or deterioration"? 



3d. How is the deterioration, if existing, to be prevented and thelbeds improved? 



In the endeavor to answer these questions it was necessary to investigate many problems and 

 to collect much information haviug apparently but little bearing upon the main question, but it 

 was my endeavor to limit the extent of the inquiry as much as possible and to direct all the ener- 

 gies of the party to the decision of the three points mentioned. 



Though the biology of the oyster should be studied, yet only so much of it was essential to the 

 work he had undertaken as would assist in the solution of the problem presented, and consequently 

 it was desirable to leave an extended investigation in that line to others and to settle ourselves 

 only such points as would, as far as we could see, directly assist us in arriving at correct con- 

 clusions. 



The investigation conducted during the summer and autumn of 1878 had shown that the beds 

 were deteriorating rapidly, and so far as could be seen the principal cause for this deterioration 

 was the over-fishing of the beds. The remaining question to be answered was, then, how the dete- 

 rioration was to be prevented. 



The main cause was decided to be excessive fishery, which, by removing too large a number of 

 mature brood oysters, diminished in a constantly increasing ratio the fecundity of the bed. Other 

 causes operated also to some extent, but their effects were inconsiderable. 



There is but one method of maintaining the fecundity of the beds, and that is by protection, 

 but this protection can be afforded in several ways: Either by restricting the fishery, by enlarging 

 the field for the dredgers, or by insuring the maturity of a larger number of oysters, by artificially 



