OYSTERS AND METHODS OF OYSTER-CULTURE. 307 



and oystermen attribute tbis to the fact that the shells project a greater 

 distance above the bottom and that therefore the fry come into contact 

 with them first in their descent for attachment, but as the set is mainly 

 upon the convex side of the shell and therefore underneath^ it will be 

 seen that the true explanation of the superiority of the shells is that 

 given above. 



The quantity of shells sowed upon any given bottom will depend upon 

 the judgment of the i)lanter, the general rule being to sow more on soft 

 than upon hard bottom, for the reasons before stated. The usual quan- 

 tity appears to be from 250 to 500 bushels of shells per acre, most of the 

 planters using about 400 bushels per acre, except upon very muddy 

 bottom; but in Long Island Sound there is an increasing tendency to 

 use greater quantities. 



In some places the shells may be obtained for the cost of transporta- 

 tion. This was the general rule years ago, but with the increase in 

 planting a charge of from 2 to 5 cents per bushel is now made for them. 

 Many planters who operate canneries or ship "shucked" oysters have 

 ready at hand an abundant supply of shells for use as cultch. The cost 

 of spreading ranges from J to 2 or 3 cents per bushel, according to the 

 location of the beds and the cost of labor, etc. 



The principal objection to the use of oyster shells is that they are of 

 such large size that many more spat attach themselves than have room 

 to grow and, at the same time, they are so strong and massive^that it is 

 difficult to break them in pieces so as to allow for the expansion of the 

 young. As a consequence many young oysters which have successfully 

 passed through the early stages of their fixed conditions are smothered 

 or overgrown by their more vigorous fellows, which are themselves dis- 

 torted by the crowding to which they are subjected. Many are thus 

 wasted which would, under better conditions of attachment, have grown 

 to a marketable size. (Plate ix.) 



For the reasons mentioned scallop, "jingle," and other fragile and 

 friable shells (plate xviii, figs. 1 to G) are, when they can be obtained in 

 quantities, to be preferred. Such shells will break up under the mutual 

 pressure exerted by the oysters during their growth and the latter will 

 then be liberated from the bunches and will tend to grow into shapely and 

 desirable forms, with a smaller rate of mortality. When the currents or 

 waves are very strong such frail shells as jingles may prove too slight 

 to withstand their action and the planter using them may find, to his 

 surprise, that much of his cultch has been carried away. Upon some 

 portions of the Pacific coast it is said that the wave action and the 

 currents are so strong that the light, thin shells of the native oyster are 

 swept away or thrown upon the shore. Otherwise, and for the reasons 

 before stated, these shells appear to be well adapted to the process of 

 sowing and they can also be obtained cheaply and in large quantities. 



Other methods of using shells. — It has been recommended or suggested 

 that shells of various kinds could be strung upon wires, etc., and sus- 

 pended in festoons from stakes planted in the bottom. This would, of 



