220 THE FISHERIES OF THE UNITED STATES. 



"They are usually dark in color, and have a considerable amount of mud and sand on the shells. The sponges do 

 not appear to be as abundant, and the amount of dredging on any bed may always be known by the appearance of 

 the oysters brought up. Upon an overdredged and almost exhausted bed the oysters will be large and single, 

 blunt-billed, with dirty shells, and an almost entire absence of sponges, barnacles, and Crepidula will be noticed, but 

 the shells will be covered with TuMcola and bored in many places by the horing pholadJ' 



Oystek peakls. — As in other mollusks, pearls are likely to be found in onr common oyster, but, unfortunately, 

 these are usually discovered in the mouth after the oyster has been cooked, and the value of the pearl thus destroyed. 

 In the Peabody Museum at Yale College is a hollow, tear-shaped pearl taken from a common oyster at New llaven, 

 which is a third of an inch in length. Mr. Ilenry C. Eowe, of the same city, showed me several large, round i)eai-ls, 

 and told me he had had a hundred or so in the course of his life. As a rule, however, they have little market value. 



Oyster-beds. — Inasmuch as oysters can only exist under certain conditions, to be found only in restricted 

 areas of sea-bottom, it is naturally to be expected that they will be found in colonies having a boundary defined 

 with more or less exactitude. These restricted localities, because of their usual shai)e and appearance, are called 

 "beds" and "banks" in the northern states, and "bars" or "rocks" in the southern, while in the Gulf of Mexico 

 you hear only of " oyster-reefs ". Although in waters so populous with this mollusk as Chesapeake bay, a floating 

 plank or bush will be found covered with small oysters in almost any part of the bay, it would be far from the truth 

 to conclude that even in that most favored region the bottom was paved with the bivalves. On the contrary, the 

 beds there, as elsewhere, are so well marked that they can be laid down on a chart or staked out with buoys; and 

 even in the best oyster-regions they occupy such an inconsiderable part of the bottom that any one ignorant of 

 their position would have very little chance of finding oysters by promiscuous dredging. At the same time, it is 

 not always apparent why an oyster bank should occur where it is found, rather than at some other place ; or why 

 many areas, seemingly highly suitable, are not furnished with them. In the beginning, the character of the 

 bottom has the greatest influence of all upon the location of a bed, undoubtedly, for a young oyster will not live 

 except in certain suitable situations. Accident having fixed an oyster in a certain spot, however, and good fortune 

 granted him safe growth, the growth of a bed there follows speedily, and with widening area augments in strength, 

 until nearly beyond the reach of natural destructive agencies. The living and dead shells of the adult oysters 

 furnish the best surfaces for the attachment of the young, and for this reason the points where oyster-beds are 

 already established, are those where the young have the most favorable surroundings and the best chance for life, 

 and the beds thus tend to remain permanent and of substantially the same size and shape. An idea of their extent, 

 under favorable circumstances, may be had from the report to the Coast Survey, that in Tangier sound, Maryland, 

 alone, there are 28 beds, whose united area is 17,976 square nautical miles, with twice as much additional bottom 

 where oysters are occasionally caught. 



Effect of sedimentary deposits upon the beds. — The welfare of the beds is interfered with, seemingly, 

 by few natural influences outside of living enemies. Mr. Winslow investigated the question of sedimentary deposits 

 upon the beds of a portion of the Chesapeake, and reports in respect to Tangier sound as follows : 



Those beds lying in deep water are particularly free from an undue proportion of mud on the bottom, the shoalest beds having the 

 thickest mud-eovermg. If there was a constant and increasing deposit upon the beds, they would long ago have disappeared, or at least 

 have become of much smaller area, but the reverse is the case, the beds increasing in area constantly. 



They are, however, exposed to one species of deposit which is very injurious. Heavy gales occurring in winter and summer frequently 

 tear up the large quantities of grass, sea- weed, and si)onge on the sand shoals about the sound and deposit it upon the beds. If this occurs 

 in suumier, wheu there are a smaller mimber of dredgers at work, the effect is very injurious, the "cultch" being covered, and the young, if 

 spawned, smothered by the grass, weeds, sand, and mud which it collects. The California rock, Piney Island bar, and Manokin lieds are 

 those most subject to this evil. The gales also have the effect of covering the scattered oysters on the leeward sands, which process is 

 called "sanding", and, from what I could learn, appears to be a very injurious one. The oysters are buried, and the bottom becomes 

 smooth and hard. Where at least thirty bushels of oysters could be taken previous to a gale, not one oyster could be found subsequent to 

 it. The winter gales have the greatest effect, owing probably to their greater severity and direction, which is from the northward and 

 westward. The "sand" oysters are found in largest numbers on the eastern shores of the sound, and about Kedge's and Hooper's straits, 

 consequently they would feel a northwesterly gale nuich more than one from the opposite direction. They are said not to recover from 

 the "sanding" for sever.al months, and upon their reappearance are noticeable on account of the whiteness of their shells. 



In respect to Pocomoke sound, more harm was disclosed : 



The fact that on nearly all the beds, and especially those in the vicinity of the creeks and rivers and in the upper part of the sound, 

 there is a light covering of mud more or less thick over the oysters, would lead to an inference that there must be a dcjiosit of that 

 character going on. On most of the beds the substratum of the bottom was hard, and the thickness of the surface covering gradually 

 decreased as the entrance to the sound was approached. » » » The Pocomoke river, draining an extensive tract of the peninsula, 

 would bring down a large amount of sediment, which tlui strong ebb-current would carry directly over the beds in the upper part of the 

 sound. The amount in any given period of time would be dilficult to ascertain, but the character will bo shown to some extent by an 

 examinatiou of the specimens of bottom. WluUher the amount of matter deposited is sutlicient in quantity to seriously attect the beds is 

 a matter of conjecture. I should judge that it wan not, and my opinion coincides with tliat of all the oystermen I was able to interrogate. 



That it must have some effect caunot bo doubted, and the evident deterioration of the l)eds in foconioke sound may lie accouuted 

 for, to some extent, by the supposition that the effect is injurious ; but so many other and more direct caaises exist for tlie (l(^teriorilti(ln, 

 tliat it is difficult to eliminate their inlluinice. The fact that the beds have existed and have been worked since the lirst settlement of the 

 country, would lead to an inference that Hu: el'l'ccl, if prejiulieial, was very slightly so. 



