FISHERIES OF THE UNITED STATES. [32] 



liistrated by tbe series sbowiug- <' peculiarities of growth due to abnor- 

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

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

 the effort of tbe animal to keep tbe 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 

 lalleu on one side or tbe other ; sometimes dorsal and ventral, as though 

 it bad always fallen on one edge or tbe 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 

 tbe 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 tbe growth of each indi- 

 vidual oyster. Tbe 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 "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 tbe 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 

 inire waters are much (-leaner and harder in character ; tbe shell layers 

 are thinner and less friable, and the boreal form more i)rominent and 

 frecpient. 



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

 Generally speaking, it is slower in Long Island Sound than in tbe Cbesa- 

 peake, tbe 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 tbe animal at different ages also 

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

 two characteristics are by no means constant, even in tbe 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 tbe worst during 

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

 tive merits of the crop from the various localities. 



