XX.—The Rate of Growth of<i>Venerupis pullastra</i>(Montagu) at Millport, Scotland

Abstract

Synopsis Marking experiments have demonstrated that certain of the rings appearing as surface sculpture on the shells of the lamellibranch Venerupis pullastra are valid as a measure of annual growth. From measurement of these rings the mean monthly and the mean annual growth increments have been calculated. The length-age relationship curve is similar to that of most other lamellibranchs. Reasons for the variation in the mean monthly rate of growth have been examined. The height-length and the thickness-length ratios for various sizes have been calculated and found to follow a simple and direct tangent relationship.