1. The problem of the relationship between the size of the plant body and the size of the organs it produces has been studied by various workers, who find that in most cases there is a small but significant correlation between these characters. 2. In a series of bean plants, the coefficients of correlation were determined between plant size, as measured by dry weight of shoot, dry weight of fruit, number of leaves, number of pods and number of seeds; and the average dry weight per plant of leaf, pod and seed. A positive and significant correlation, though usually a small one, was found in each case. 3. An examination of the curve of means for organ size on plant size shows that in each case the curve rises steeply at first and then flattens out. In other words, an increase in the size of the plant is accompanied by an increase in the size of its organs if we consider comparatively small plants only; but after a certain size is reached, any further increase in plant size is not followed by increase in orga...