Bull. U. S. F. C. 1890. Oyster-culture in France. (To face page 363.) 
Plate LXVIII. 
Figs. 1, 2. Flat Oyster, Ostrea edulis. Specimen from Belon, two and a half years old. Natural size. 
Limit of size of edulis is about 4" X 4". These old individuals were formerly regarded as a distinct species, pied de cheval, 0. hippopus. 
Figs. 3, 4. Portuguese Oyster, Ostrea anqulata. Specimen from the Tagus, xj. (Page 365.) 
(Figures from drawings by the author.) 
