[15] OYSTER-CULTURE IN THE MEDITERRANEAN. 921 
Their growth was apparent during the whole of last year, and it was 
_ also observed with satisfaction that they had propagated. I, myself, 
found some very young ones on the cords of tunny-nets. It is thought 
that the spat of this mollusk floats freely in the water, until it is stopped 
by some obstacle, to which, however, it does not adhere; it remains free 
in the interstices which have received it. As soon as it becomes more 
developed, it leaves its place of refuge, where it found neither the food 
necessary to its growth nor the protection it needed against its enemies, 
and settles in the sand or among the vegetation. The namesimple praire 
has been improperly given to the Cardita sulcata, for it is neither the 
parent nor the congener of the double praire, but belongs to a distinct 
species. The simple praire does not exceed in size the cockle (Cardium 
edule), which, as regards its shell, it strongly resembles; its flesh, how- 
ever, is of a reddish color and has a rich flavor. When placed in the 
same parks as the double praires, they have gone on reproducing their 
kind from the first year of their introduction. By digging in the sand 
on the shore, and as far out as the ropes of the tunny-net (madragque), 
we found some that measured from 5 to 7 millimeters (4 inch) in diam- 
eter, as early as the’month of September. The fishermen say they had 
never previously found this mollusk on this part of the shore of Giens, 
The acclimation of the simple praire is now an accomplished fact, and 
shell-fish culture cannot but be benefited thereby. 
The clovisse of Toulon and Cette have also increased much in size 
during the pastsummer. Indications of their spawning have been found 
near where they are located, and still more abundantly on the ropes 
supporting the nets of the madrague. In autumn the new generation 
had attained a size of from 10 to 12 millimeters (about 4 inch). 
The clovisse of Toulon, which has a dark and hard shell, lives in limpid 
waters and on a sandy bottom. The clovisse of Cette, whose shell is 
thinner, more tender, and lighter in color, lives in less pure water and 
‘on more earthy bottom. I will relate, simply for the sake of recording 
the fact, an observation made at Giens, which it is difficult to explain, 
regarding the manner of reproduction of the shell-fish in question and 
their well-defined characteristics. It would appear that the clovisse 
imported from Cette has a tendency to resemble the clovisse of Toulon; 
that is to say, to borrow from it something as regards shape and color. 
Although the possibility of a crossing may be contested, it must be ad- 
mitted that the bottom on which the clovisse from Cette now lives, and the 
quality and nature of the food which they find there, may have caused the 
modifications to which Ihave justreferred. Atallevents, it is proved that 
after a very short sojourn in the parks at Giens, they have acquired the 
flavor peculiar to the native variety. There is another fact to which it 
seems proper to call attention. It was observed that the spat had par- 
ticularly sought out the ropes of the tunny-net (madrague) at consider- 
able distances from the concession. In the beginning of winter, when 
the madrague was taken up from the water, some of the ropes were so 
