21 G FISHERIES OF THE UNITED STATES. [32] 



lastrated by the series showing " peculiarities of growth due to abnor- 

 mal influences or change of position subsequent to time of attachment." 

 As shown by some of the specimens, owing to change of position, and 

 the effort of the animal to keep the tips of the valves uppermost, the 

 shell has two and three distinct changes in direction of growth, and 

 these changes are sometimes lateral, as though the shell had always 

 fallen on one side or the other ; sometimes dorsal and ventral, as though 

 it had always fallen on one edge or the other ; and sometimes the irreg- 

 ular growth is a combination of both. This peculiarity is more fre- 

 quent in oysters from cultivated than in those from natural beds ; but 

 it is more marked when it does occur with the natural oysters than with 

 the cultivated ones. As the cultivated beds are more continuously and 

 systematically raked, probably each oyster is turned over once or twice 

 a year, and seldom has an opportunity for any peculiarity of growth to 

 become decided. The natural oyster, however, is rarely handled much 

 before being conveyed to market, and consequently any unusual growth 

 forced upon it is apt to be very remarkable. 



The character of the bottom has not only a very decided influence 

 upon the growth of the beds, but also affects the growth of each indi- 

 vidual oyster. The shells from impure, muddy waters, are usually dull 

 colored and soft or friable, and when the bottom is very soft, the long 

 flat growth is the only form that has any chance of survival. Types of 

 this form, the l ' pinched" oyster of the fishermen, are exhibited. A large 

 amount of soft mud, either in the water or on the bottom, likewise affects 

 the interior shell-layers. Particles of the muddy soil get between the 

 valves and under the mantle, and the animal builds a thin layer of shell 

 over them, causing thus the dark blue and black spots about the edges 

 of the shells and over the interior surface, so noticeable in specimens 

 from muddy localities. These peculiarities are shown in the series 

 illustrating the effects of soft bottoms. Shells from hard bottoms and 

 pure waters are much cleaner and harder in character ; the shell layers 

 are thinner and less friable, and the boreal form more prominent and 

 frequent. 



The rate of growth of the American oyster varies with the locality. 

 Generally speaking, it is slower in Long Island Sound than in the Chesa- 

 peake, the northern oysters not being considered fit for market until 

 three or more years old, while in Maryland and Virginia waters they 

 attain a marketable size in a year and a half or two years. They are, 

 however, at that age, quite small and are used for steaming or inferior 

 grades of "packed" stock. The size of the animal at different ages also 

 varies with the locality, as does the quality and flavor; but these last 

 two characteristics are by no means constant, even in the same locality. 

 For instance, oysters from the Blue Point district, or Long Island Sound, 

 may be the best in the market during one winter and the worst during 

 the next. Only actual inspection, each season, can decide the compara- 

 tive merits of the crop from the various localities. 



