OYSTER CULTURE IN FRANCE. 565 



hend ponds, depots, and claires. The ponds are little 

 establishments of 400 square metres, surrounded by walls 

 of unmortared stone, 20 centimetres high, situated on the 

 shore, and washed by the sea at each tide. The depots are 

 established on the muddy flats of the shore ; they are 

 limited by branches of tamarind, stuck in the mud, which 

 at the same time serve as a line of demarcation. The 

 claires are basins dug on the banks of the Seudre, from 30 

 to 35 centimetres deep. 



The earth which has been taken out serves to form the 

 slope, the summit of which is about i metre from the bot- 

 tom of the reservoir. They are divided into high and low 

 claires ; the low claires, nearer to the bed of the Seudre, 

 receive the water pretty frequently ; the high claires, further 

 from the arm of the sea, and dug on ground comparatively 

 higher, are only supplied during four or five days at 

 springtide. 



The greater number of claires are surrounded by a 

 trench independent of the small streams (ruissons) of 

 alimentation ; into which are thrown the slimy deposits 

 washed up by the sea. 



The depth of the claires, I have said, varies from 30 to 

 35 centimetres ; but in the autumn the water is not kept 

 higher in them than from 24 to 30 centimetres. When the 

 cold weather arrives, this depth is increased, for the frosts 

 and snow are very severe, and the ice is immediately 

 broken if it covers the reservoirs. 



The low claires turn green first ; this condition lasts 

 from the month of September till the month of February ; 

 the high claires turn green in the month of November, and 

 lose their colour towards the month of April. 



