OYSTER-CULTURE IN FRANCE. 
377 
oyster’s feeding' conditions along tlie flats at Cancale are certainly noteworthy. During 
my visit the lower sands were streaked and mottled with a golden-brown crust of 
diatoms. 
The second kind of barrier park prevails at Arcachon, by far the most important 
seat of oyster- culture (Plate lxxiii, Fig. 2, and Plate lxxiv, Fig. 1). The first figure 
shows one of M. Daste’s parks. The fascines of twigs seen banking the inclosure have 
been implanted in the hard sand of a little emerging island, a crassat. The park bottom 
is hard, and for that reason draining trenches are not formed. About 10 inches of water 
is retained to cover the oysters. The other figure represents the employes at work 
and shows the way in which the small parks are grouped. One of the curious fea- 
tures of Arcachon is a boundary fence, formed of waving saplings, a device intended 
either to frighten away injurious fishes or to retain them as the tide falls. An illus- 
tration (Plate lxxv, Fig. 2) shows the sapling fence on either side of an alleyway, 
imposed by law, separating adjacent parks, to serve for transport. The oyster boat of 
Arcachon (Plate lxxv, Fig. 1) is the ancient pirogue of the Basque region, often provided 
with lateen sails — half dory, half gondola — a capacious affair, heavy in build, but 
curiously light to handle. At the boundary of each park is located a guard boat or 
ponton, one end of which contains the guard and his dogs; the other end serves as a 
workshop. 
An illustration (Plate lxxvi, Fig. 1) shows the character of the most costly type 
of oyster park, a lake surrounded by well-slanted stone walls. It is the bassin des 
chasses&t Sables d’Olonne, half of whose area of 160 acres is devoted to oyster-culture. 
As a park it illustrates several novel points well worthy of discussion. It is, in the 
first place, a compound or cooperative park ; that is, it includes a myriad of smaller 
parks and has an organized management. Its central government, supervised by the 
ministry of marine, regulates the important matter of water supply and rents out 
tracts to the culturist. This annual rent, about 2 cents per square foot, is understood 
to include the general expenses of water supply, guards, and necessary repairs. The 
parks are for elevage, the greater part of the seed coming from the region of Auray. 
The planted beds remind one curiously of those of a market garden, well banked and 
separated by trenches. These serve to collect the depositing sediment conveniently 
for removal. The bottom, however, is naturally level and hard, a firm mixture of sand, 
mud, and clay. This large park again illustrates the principle spoken of in regard to 
Breneguy, that a large surface allows the water to aerate without constant renewal. 
The management permits change of water during only three days consecutively per 
week. The great gates are first opened to allow the water to pass out until only about 
a foot of water remains above the oysters; the rising tide is then admitted to the 
depth of 4 to 6 feet and the gates are closed. The water is comparatively shallow 
and becomes warmer; germination and growth of plant life speedily ensue and furnish 
the best of feeding to the inclosed oysters. This is attested by the rate of growth and 
fattening that the oysters are here remarkable for, a pousse sometimes as great as 
half an inch per month. The culturists themselves note that if the water is shallow 
and warm the growth of the oysters may be forced as that of the plants in a hotbed. 
There is danger, however, that the water, if shallow, might become too salt by reason 
of evaporation, or too freshened by reason of continued rains, and therefore a depth 
of 4 feet is normally maintained. Aeration and living conditions become then so per 
