53 



"In conclusion, I hereby give as the foundation for all oyster culture the most important rules 

 for the improvement of the natural oyster banks. 



" First. An oyster bank will yield permanently the greatest profit if it possesses such a stock 

 of full-grown oysters as will be sufficient to maintain the fecundity of the bank in accordance with 

 its bioconotic conditions. 



"Second. When the natural conditions will admit of it, the yielding capacity of an oyster bed 

 may be increased by improving and enlarging the ground for the reception of the young brood. 

 The natural banks should be improved by removing the weeds and plants with dredges and 

 properly constructed harrows, and by scattering the shells of oysters and other mussels over the 

 bottom. When circumstances will permit, all the animals which are taken in the dredge, and 

 which kill the oysters or use up their food, should be destroyed. It would be much more judicious 

 and much better for those who eat oysters if the 'close time' could be extended until the 15th of 

 September or the 1st of October, so as to allow the oysters some time after the expulsion of the 

 contents of the generative organs to become fat before being brought to the table. If it is desired 

 that the oyster banks should remain of general advantage to the public and a permanent source of 

 profit to the inhabitants of the coast, the number of oysters taken from the beds yearly must not 

 depend upon the demands of the consumers or be governed by high price, but must be regulated 

 solely and entirely by the amount of increase upon the beds. The preservation of the oyster beds 

 is as much a question of statesmanship as the preservation of forests." 



INVESTIGATION CONDUCTED DURING THE SUMMER AND AUTUMN OE 1879. 



My assistants during this season were Master H. H. Barroll, U. S. IS.; Ensign W. H. Allen, 

 U. S. N. ; Mr. W. E. W. Hall. 



Mr. Barroll had charge of the compilation and arrangement of the statistics collected, and, 

 in the field, general charge of the work during the absence of the chief of the party. 



Mr. Allen calculated the number of oysters to the square yard, and the ratios between the 

 classes; he also tested the water specimens and developed the curves illustrating the changes and 

 range of density. 



Mr. Hall was charged with the care and arrangement of the records so as to facilitate their 

 study by myself and others. 



INSTRUCTIONS. 



The instructions of the Superintendent, issued June 30, 1879, desired that the vessel and party 

 should proceed, as soon as possible, to the lower Chesapeake Bay, and continue the investigation 

 begun and prosecuted during the previous season. The instructions were concise, and, being sup- 

 plemented by verbal ones, were expressed in general terms. It was intended that the scope of the 

 investigation should include as much of that called for in the instructions for the previous season 

 and such additional matter as the judgment and experience of the chief of the party should dictate. 

 The vessel sailed from Baltimore, Md., for Tangier Sound on July 3, 1879, and the field work was 

 completed on the 30th of October, when she arrived at Philadelphia, Pa. 



PLAN OF WORK. 



In devising the original plan for the work of the season it was expected that, not only would 

 the party be much larger than it actually was, but that it would be in the field much earlier in the 

 season. This original plan was, briefly, as follows: One division of the party, in a small steamer, 

 was to continue the delineation of the beds and the search for such new ones as might exist. The 

 extension of the survey was to be from Tangier Sound along the eastern shores of the bay. 



The other division of the party was, in the Palinurus, to continue the study of the beds already 

 surveyed, the conditions affecting the oysters, and determine, if possible, the effect of changes of 

 temperature and density upon the production and subsequent life of the spat and mature oyster. 

 They were also to ascertain what was the increase in size of the oyster in a given time, and deter- 

 mine the number of oysters surviving in each successive period of life, or establish the natural 

 ratios between the different classes. It was also intended that this branch of the party should 



