804 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [52] 
sible to prevent the deposit of mud, the breeders always have certain 
unoccupied claires into which they transfer the oysters from the muddy 
claires while these are being cleaned. After a thorough cleansing they 
are left empty until it becomes necessary to clean the other claires, 
when the oysters are transferred back to their old quarters. But cer- 
tain of the breeders, not willing to allow portions of their land to lie 
unproductive, content themselves by cleaning the bottoms and then 
replacing the oysters in their old inclosure, always soiled with mud. 
It is useless to enumerate the defects of this practice, which can only 
produce inferior results both as to quality and numbers. 
Such, in a few words, is the industry of the breeders of Marennes, 
and it is this which we shall take as a guide, if not as a model, for 
debarring certain imperfections, it presents the most rational and best 
combined principles. If the breeders were in the habit of obtaining the 
germs necessary to restock their claires from the claires themselvas, if 
they had constructed their ponds so as to be able to raise the level of 
the water contained in them from one and one-half to two meters, and 
had subjected the water from each tide to a certain amount of stagna- 
tion before entering the claires, so that it would carry with it as little 
mud as possible, there would be nothing lacking in their methods; it 
would simply be necessary tocopy them. Letus profit, then, by all that 
is valuable in their industry, such as it is ; let us borrow from the claires 
all that can be borrowed, all that long experience has proved efficacious, 
and then add the improvements suggested by our recent studies, and 
with these elements combined we shall have an excellent guide for 
the future service of breeders in constructing and working their claires 
and live-ponds. <A claire or live-pond can be established upon any 
ground where the altitude above the level of the sea is sufficient to ena- 
ble it to be covered by the tide, not every day, which would expose 
it to a too frequent deposit of mud, but at least twice per month and 
during five or six days each time. And as a breeder should never be con- 
tent with one claire, however small his establishment may be, a series 
of basins can be made, either in one or two rows parallel to the coast, 
along the surface sloping to the sea, and all having the same level. It 
would not be prudent, however, to have somany that it would be neces- 
sary to place them at different levels, or in the form of steps, since in 
this case. the lower ones would receive water more frequently, and 
even be submerged and exposed to a more frequent deposition of mud, 
while the upper ones would receive very little water. But if it becomes 
necessary to construct claires in a series of steps at different levels, 
either because of a restricted amount of surface, or to utilize pre-exist- 
ing basins, they ought never to be used indifferently for oysters of all 
ages, because the conditions offered by the upper basins would be much 
more favorable for young oysters, and only when they have attained acer- 
tain size and a greater degree of vitality should they be placed in the 
lower apartments. The soil of the bottom of the claire demands, ac- 
