of the Fishery Board for Scotland. 
227 
stage of removal from the tiles the young oysters, if not protected would 
become the prey of the star-fishes, the crabs, and the boring molluscs. To 
prevent the ravages of these enemies all ostreiculturists of any note adopt 
special measures. The young thin-shelled forms are transferred to cases 
or ambulances — caisses ostreophiles — which are set down in the water. 
These cases costfrom ten to fifteen francs, and were the invention of M. 
Michelet of Arcachon. They are formed of four pieces of wood — four to 
six inches broad — nailed together to form a framework, two to three feet 
broad and four to six feet long ; to this framework is fixed a bottom of 
galvanised wire-cloth, and there is often a lid of the same material to close 
the case. Generally there are four legs on the case to permit of its stand- 
ing a few inches above the ground. 
The oysters remain for a longer or shorter time in these cases. They 
may be transferred to the claires, which at Arcachon average from 50 to 70 
metres long by 10, 15, and even 30 metres broad. At Arcachon these 
claires are formed by being enclosed by walls of clay about a foot high. 
The clay face being secured either by boarding or by a breast- wall of 
heather on the outside. They remain in the claires till they are transferred 
to the fattening and growing grounds. Arcachon natives are sent to 
Marennes, and La Tremblade to be greened and fattened, and to He 
d'Oleron and other places to be fattened. The oysters of the 
second great centre of reproduction in France — the Morbihan, compris- 
ing Vannes, Auray, St. Philibert and La Trinite — are sent to the greening 
and fattening establishments at Marennes and La Tremblade, or to more 
northern places, such as Whitstable and the ports on the French side of the 
Channel. Of course, some of these are also made ready for the market 
near their birthplaces, but Arcachon and Brittany are essentially for the 
production of the spat. 
In Holland great quantities of spat are produced in the East Schelde ; 
many are fattened on the Yersche Banks, and many are exported to the 
fattening grounds of Essex and Belgium. 
The Growth and Fattening of the Oyster. 
The conditions necessary to growth and fattening differ somewhat from 
those required for breeding. While reproductive activity requires the 
water to be of high specific gravity, and a high temperature, if there is 
to be a large and plentiful supply of spat; oysters will flourish and fatten 
in waters that are neither so warm nor so exclusively salt. Mud, 
which has been seen to be so hurtful to young oysters may be exceedingly 
helpful to adult forms. In France especially, the oyster industry is 
divided into two very distinct branches, either of which, if carried out in 
an enterprising and intelligent manner, is successful. The French have 
for long perceived this, and many ostreiculturists devote themselves to one 
branch almost exclusively. If this fact had not been so often lost sight of, 
the ventures that have been made in England and in Ireland would not in 
so many instances have failed. 
The chief fattening ground of France is situated to the north of the 
Gironde, in the Charente Inferieure, in the districts of Marennes and La 
Tremblade. There are other localities in the north, especially along the 
shores of the English Channel, where fattening operations have also been 
and are most successful. The Dutch can fatten their oysters at Yersche, 
in the neighbourhood of the spatting ground. They send them to Ostend, 
Whitstable, and Colchester, where the different ' natives ' are fattened. 
It will be sufficient, however, to describe the fattening operations at La 
Tremblade and Marennes. These two places are chiefly famous for the 
