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Ground most suitable for the collection of spat is 

 usually found wherever a strong current courses along 

 the margin of a flat or crassat. Wherever such a scour 

 is specially well marked, collectors there placed keep 

 clean and free from glairy sediment and so present 

 suitable surfaces for spat attachment ; this appears to me 

 the special virtue of this position. Usually the location 

 for the crate-like collector cases solely employed at 

 Arcachon has a soft mud bottom, so soft that the parkers 

 wear wooden plates attached to the feet to prevent sinking 

 too deeply. This bottom requires no preparation other 

 than the driving in of six short piles to serve as a 

 foundation for each collector-crate which it is intended 

 to install. Each pile is driven from 2 to 3 feet into the 

 mud, its upper end projecting a few inches above the 

 surface. 



For rearing the brood oysters after stripping from 

 the tiles, the higher and central portions of the flats are 

 best adapted whenever the surface is firm and not excess- 

 ively muddy. At the present day practically all the suit- 

 able lots have long been in occupation and are now in 

 prime condition. Prior to the advent of culture and when 

 natural oyster beds still flourished in the basin, the 

 greater proportion of these flats were occupied by oysters 

 forming" extensive areas of hard well-consolidated surface 

 from the long continued accumulation of the dead shells 

 of former generations. The reckless and unrestrained 

 exploitation that occurred during the first half of last 

 century gradually reduced the thickness of this stratum 

 of hard material ; the dead and living shells forming the 

 bed were the only cultch for spat to attach to, and with 

 the inroads made on the bank every year so large an 

 amount of this natural cultch was removed ashore and 

 never replaced that the surface of the flats suffered 

 appreciable degradation and very great deterioration 

 from a cultural standpoint. To improve the areas 

 selected by Coste as " State model farms " large quantities 

 of cockle shells were spread over the surface to help to 

 consolidate it. Fortunately however it was found that if 



