OYSTER AND MUSSEL REPORT. 115 



is teeming with microscopic life, and it is probably this 

 rich feeding alone which is necessary in order to bring the 

 oysters in a very short period — a few weeks usually, some- 

 times 10 days or a fortnight is sufficient — to the desired 

 condition of fatness and flavour. 



It is said that the oyster can be coloured under favourable 

 circumstances in 36 hoars. It is only the gills and the 

 labial palps of the animal which become green. The 

 pigment of the Diatom (which has been called " marennin " 

 by Prof. Ray Lankester) is really blue, but when deposited 

 in minute granules in the yellowish coloured gills it gives 

 rise to the greenish tint. 



From the oyster's point of view the claire is a very 

 unhealthy place. The mortality is very high, and those 

 that survive are probably in an enfeebled, if not actually 

 a diseased, condition. They have had far too much to 

 eat, their food is highly nutritious, the water is very 

 stagnant and badly aerated, and is probably unhealthily 

 warm. However the healthy natural oyster is not what 

 is desired by the epicure, and of course it is the business 

 of the eleveur to produce what will fetch the highest price 

 in the market, so he regulates the condition of the claire 

 in such a way as to favour as much as possible the pro- 

 duction and growth of an abundant supply of microscopic 

 plants and animals. 



The oysters are generally laid down in the claires in 

 August, and the autumn and even early winter months 

 are supposed to be the best times for " greening." During 

 my visit in July most of the claires were being prepared 

 for the reception of the oysters, but some were full. I 

 found very considerable differences in temperature and 

 specific gravity between some claires and others, as is to 

 be expected when one recollects that the fresh supplies 

 of water are admitted at very irregular intervals, so that 



