THE OYSTER-INDUSTRY. 217 



Some more fragile shell, such as a scallop or mussel or jingle (Aiiomia), is certainly better, because the growth of 

 the attached oysters wrenches the shell to pieces, breaking up the cluster and permitting the singleness and full 

 development to each oyster that is so desii-able; or, if the old shell does not break of itself, the culling of the bunch 

 it supports is far more easy than when the foundation is as thick and heavy as an oyster's or clam's shell. To aid 

 this same end, tiles have been used as collectors of oyster-spat, which were covered with a certain composition which 

 easily peels off, but which is firm enough to hold the young. When they have attained a size and age fit for 

 removal, they can be stripped off without difBculty, removed to other quarters, or deposited in the localities used 

 for growing or fattening, and the tiles can be re-covered with the composition and used again. (In the Chesapeake 

 it is found that the under-side of the tiles catch the most spat.) Possibly, for a permanent bed, nothing is better 

 than the natural shells, but, to catch the floating spawn, something of this sort might be tried to advantage, 

 especially when it is desirable to move the young oysters, either to protect them from enemies or to grow them 

 separately. The anchoring of an old seine at the bottom, the suspending of scalloi^, cockle, or other thin shells 

 in the water, by stringing them from stake to stake a little way under the surface, or the copying of the French 

 "fascines", would be other means to the same end. One of my correspondents in Long Island suggests inclosing 

 small beds of oysters, just before spawning, by a high board fence, "with plenty of shells or scraps inside to catch 

 the spawn, which thus could not float away". This idea is substantially followed in France, where stakes of wood 

 are driven into the bottom in a circle around a pyramid of oysters placed on stones in the center; and on the He de 

 Ee dikes are built of open stone work, so as to divide the bottom into beds, each of which is owned by a jirivate 

 ])roprietor ; and other stone partitions or walls are run across, and upon these stones the spawn fastens. There 

 are 4,000 of these beds or jmics. 



The early experiments in making these artificial beds failed, through the error of placing the cnltch in the water 

 too soon. Before the oysters near them had spawned, the insidious but rapid deposit of the water had coated them 

 with a greasy slime, which made them as unfit for the attachment of the larvae as any part of the surrounding 

 bottom. Thus it was learned that the cultch must be deposited as short a time before the emission of the spawn 

 as possible. 



TniE OF sPAWNiTs'G. — The time of spawning was found to be variable at different latitudes, in different depths 

 of water, and according to diverse conditions of weather, etc. It seems to depend primarily upon temperature; 

 hence, in the south, it begins as early as the heat of summer comes on, and follows it northward. In Chesapeake bay 

 spawn has been collected from Apiil until October. In the report of Jlaster Francis Winslow, of the United States 

 navy, concerning his surveys of Pocoraoke and Tangier sounds, in the Palinurus in 1878, it is stated that there the 

 spawning lasted from May to xVugust, but occurred chiefly in June and July. "All opinions coincided that the 

 oyster in shoal water spawned fli-st, but diiiered as to wlfether, the depth being the same, all oysters on the same 

 bed spawned at or about the same time, as many being for as against the th eory." In regard to this point I wiU 

 insert a statement from the London Standard, September, 18G8, to the eftect, that at the oyster pares on the He de 

 Ee, France, "every bed has its own time for spatting; thus, one division of the Ee beds may be spatting on a fine, 

 warm day, when the sea is like glass, so that the spat cannot fail to fall, while on another portion of the island, the 

 spat may fall on a windy day, be thus left to the tender mercy of a fiercely receding tide, and so be lost, or fall, 

 mayhap, on inaccessible rocks a long way from shore''. Mr. Winslow was also told that currents had no effect 

 upon the spawning, yet that heavy freshets were very destructive to the "spat" in Pocomoke sound, driving it out 

 into the bay, and large schools of fish, especially trout and taylors, de^'oured a good many every spring and 

 summer. I have seen it asserted, in reference to the French and English coast, that the spatting of the oyster 

 there does lot depend on the weather at all, but it certainly does here, to a certain extent, a wet "or warm spring 

 hastening tie beginning of the spawning-season, though it would not shorten its duration. 



Effect of tempkratures itpon time of spawning. — The dift'erence, too, in the time of spawning between 

 the oysters in deep water and those in shoal, is probably due to temperature, the deep water being cold and so 

 retaixling the function. As showing how temperature affects this matter, let me say that experience on the northern 

 coast shows, that when cold, windy days occur at spawning-time, there will probably be no emission at all ; but 

 when this weather changes and a night of warm rain is followed by a hot morning, thousands of oysters will be seen 

 " shooting their spawn " at once. "The selection," says Wiuslow, "of the lower sides of the tiles and the interior of 

 the 'boxes' may be an eftbrt of nature to provide some protection for the young brood by, to a certain extent, 

 inducing them to seek dark and secluded points for attachment, or the large number found in such places may 

 be due to the inability of the various enemies of the spat to get at them v. hen thus protected". 



Age of spawning oysters.— It is pretty satisfactorily proved, that oysters begin to spawn when only one 

 year old (or even much less, occasionally), though I found the popular impression in the northern states to be, that 

 they must be thi-ee years of age before emitting spat. IIow long they continue to spawn, or whether there is 

 any cessation before death, is not known, We are ignorant, indeed, of the age to which an oyster would live 

 undisturbed ; but old oystermen believe that it never exceeds twenty years, and that death is finally cauwd by a 

 continued growth of shell, until its weight and thickness become too great for the venerable animal within to 

 handle, whereupon he starves to death. 



