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MARINE PRODUCTS OF COMMERCE 



pleasant flavor and are greatly valued by connoisseurs. Green-gilled oysters are 

 regularly found in the United States on certain grounds in Virginia and North 

 Carolina. Their coloration is also due to the absorption of pigment from the algae 

 upon which they feed. But unfortunately the prejudice against green oysters in 

 the United States is so strong that discolored oysters cannot be marketed. This is 

 probably because in some places along the Atlantic Coast, as for instance along the 



(.Courtesy U. S. Fish and Wildlife Service) 



Fig. 26—3. Oyster spat of Ostrea virginica growing on a piece of tile. 

 French oyster farmers use tiles similar to that shown above and stack them 

 in large groups on tidal flats. 



Connecticut shore of Long Island Sound, oysters frequently acquire a green color 

 from absorption and storage of excess copper. In this case the green coloration is 

 not confined to the gills, but is spread around the mantle. Green oysters of this type 

 have a strong metallic flavor. In Italy the seed is caught on brushes stuck on shal- 

 low flats. 



Several types of spat collectors were developed in the United States. The most 

 promising among them are the "egg-crate" collectors, made of cardboard coated 

 with a mixture of cement and sand and a small wire bag filled with shells. The 

 American industry so far has not adopted their use, primarily because of the addi- 

 tional cost of material and labor. 



On the Pacific Coast the rapidly growing cultivation of the Pacific oyster 

 (Ostrea gigas) depends on the importation of seed from Japan. Attempts made 

 in the State of Washington to obtain seed oysters locally by using the Japanese 

 method of collecting them on garlands of shells suspended from poles placed on 

 tidal flats were only partially successful. 



Most of the oysters marketed in Japan are produced by cultivation, which 

 consists in growing oysters in cages suspended from rafts or floats anchored in 



