964 | REPORT OF COMMISSIONER OF FISH AND FISHERIES. [22] 
seven to nine months upon the collectors, are ready for removal and 
planting in beds, where they may grow and develop. The first princi- 
ple of the industry had been discovered, but the means of producing 
this seed were still wanting. 
“Then it was that [invented the cement for collectors, the formula 
of which I have given. 
“ Between the collector and the oyster there should be interposed a 
caleareous substance, hard enough to withstand the action of the sea, 
and soft enough to permit of the easy removal of the oyster at any 
time. I had proved that cleanliness was the first necessity of a good 
collector, and soon I added that the collector cement alone had the power 
of renewing that cleanliness, at the will of the oyster culturist. From 
that day oyster culture was an established fact.” 
The success attained by coating the tiles, that is to say, by dipping 
them in lime or cement, has been complete and very characteristic. 
Several culturists, wishing to observe what the difference might be, have 
placed a certain number of tiles, some coated and others not, under the 
same conditions as regards cleanliness. The former had about three 
times as many young oysters upon them as the latter. The trial was 
therefore decisive. 
In 1866, when M. de la Blanchére was seeking the principle in the 
case, he wrote: 
“A principle should govern the employment of all collecting appara- 
tus, not only as regards the time for setting the collectors, with refer- 
ence to the spawn, but also as to the special state of cleanliness of the 
apparatus itself.” 
With Dr. Kemmerer, the principle was an easy removal of the oysters 
from the tiles; with M. de la Blanchére, it was cleanliness. 
Without wishing to enter into the domain of the critic, we venture to 
say, however, that the principle had not yet been found. 
While seeking a means of easily detaching the oysters from the tiles, 
and almost without being aware of it, there was discovered the attract- 
ive element, indispensable to a good harvest, the bait, so to speak, of the 
oyster—that is, lime in an easily assimilated state. 
Such is the‘principle; we will proceed to explain it: 
When the young: oyster passes from the mantle folds of the parent, 
out into the sea, what does it instinctively seek? A place to which it 
ean easily attach itself, and where it can readily defend itself against 
its enemies. It could readily attach itself to any substance, but in order 
to defend itself, it must be able to develop its shell, which serves as a 
protective armor. As lime is the predominant element of the shell, the 
preferable collector must have a basis of lime. 
The young oyster seeks calcareous substances by instinct. Nature 
is certainly very provident. If calcareous material is wanting in the 
collector, that extremely perfect laboratory, contained within the infi- 
nitely small body, constituting the embryo oyster, will withdraw it from 
