| On two adjoining parcels, one used as a control plot, the other spread with 25 kg of phosphate "F" (followed by a light harrowing) on a one are area, we placed some grypheae aged 21 months. The molluscs are emerged for an average of 4h30 at each tide.1° it seems that, at the level used and for the first few months, the phosphate caused a physiological derangement in oysters which resulted in a higher mortality rate than in the control oysters.2° after an experimental period of eleven months, laboratory experiments showed a great similarity between the two populations. However:a) If the weight of the wet tissues is about the same, the weight of the dry flesh of the molluscs which stayed on the phosphated soil was lower than that of the control oysters.b)... |
