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of the conclusions at which I arrived in 1878, and which are 
contained in my report of the operations of that season, are 
erroneous. Some of them have been already alluded to, and 
the allusions to the remaining ones here find their most ap- 
propriate place. 
I find that my supposition that there is or was a general 
spatting on all the beds in any season to be, to a certain extent, 
incorrect. The spatting may be general, and a majority of 
the oysters may spawn each year, but the attachment of the 
young is a very different thing, and as the most precarious 
period in the life of the oyster is that just anterior to its at- 
tachment, a series of causes detrimental to the life of the em- 
bryo, while it is in its free swimming state may readily occur, 
and thus prevent such attachment. 
My investigation of the past season has proved conclusively 
that the class of oysters termed “ young growth” in my pre- 
vious report were not of the brood of 1878 but of 1877 or 1876. 
The character of the young found in both seasons, the deter- 
mination of the time of earliest attachment, and the growth 
and appearance of the oysters on the tiles, have led me to this 
conclusion. As the young do not attach before the middle of 
August, they could hardly reach such a size and shape by Oc- 
tober as would prevent their recognition as of the same season’s 
growth. 
From the inspection of the oysters taken during the last 
season, many being found as I have stated with the generative 
matter unexpelled, I am of the opinion that a combination of 
natural causes may prevent the expulsion of both the male 
and female cells, and there would consequently be no impreg- 
nation during that season. 
As I mention in report of 1878, many persons of experience 
are of that opinion, and I now concur with them in thinking 
that not only the attachment of young may not be general 
nor occur each year, but that the emission of the products of 
generation may also be frequently confined to partial areas, 
and that by a combination of circumstances there can be a 
total failure of impregnation on all beds of any locality. 
I also find by additional experience that the young oyster is 
