306 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



ofifer the largest available area for the attachment of the spat. Where 

 the bottom is so soft, however, that the shells would tend to sink before 

 the young oysters have reached a size to enable them to successfully 

 combat such <;onditions, it is preferable to surface the bottom in the 

 manner described for planting seed oysters, or the shells may be thrown 

 over so as to fall in ftat heaj^s, those at the base forming a foundation 

 support for those above, leaving only the upper shells available for the 

 set of spat, those below soon becoming buried in the mud. 



Shells may be planted in all depths of water with equal facility. 

 They are cheap and readily obtainable in all oyster regions. Clam and 

 scallop shells are also used in the same manner. The quantity required 

 to properly "shell" a bed depends upon the nature of the bottom. 

 When the ground is soft a larger number is necessary than upon hard 

 ground, because in the former case many become buried in the mud or 

 covered up by the others, whereas in the latter instance they all become 

 available as collectors. 



Upon soft ground some planters, instead of preparing the bottom 

 with sand or gravel, apply a layer of oyster shells a. couple of mouths 

 before it is time to distribute the cultch* proper. Those first applied 

 sink a short distance into the mud where they become suspended so as to 

 form a more or less solid substratum which supports the cultch applied 

 later. A bed so j)repared simulates the natural banks, which in most 

 places overlie a mud bed that, in its upper portions, has acquired some 

 consistency and firmness by the shells lying buried in it. 



After a muddy bed has been shelled for a number of successive years 

 it will be found to become gradually firmer. Each year some of the 

 planted shells become covered up and are left remaining when the 

 oysters are removed and thus it happens that the bottom of a well- 

 handled planting-ground improves with use. 



When the oyster or clam shells are thrown from the boats they will 

 be found to fall so that the convex side rests upon the bottom. There 

 is nothing very remarkable or inexplicable in this, as it is eutirely-iu 

 accordance with the ordinary laws of the resistance of fluids to the pas- 

 sage of a solid body through them; but in sowing the shells, however, 

 it is important that they so fall. In most cases, if such cultch be 

 examined, it will be found that nearly or quite the entire set of spat is 

 upon the convex or lower side. As the shell falls its greatest convexity 

 rests upon the bottom, its edge being held clear of the mud in the form 

 of a projecting ledge, sheltered on its under side from the suffocating 

 sediment deposited upon tlie upper surface. In ordinary situations 

 perfectly flat pieces of tile, shale, etc., would be vastly inferior to shells, 

 for the lower surface would lie close to the bottom while the upper 

 would become covered with a muddy deposit from the water, between 

 the two the young oyster having but scant opjiortunity tor fixa4:ion. 



It has been observed that when shells and gravel are spread upon 

 the same beds the former usually catch the larger amount of spat, 

 especially in years in which there is but a moderate set. The planters 



