a diminutive from cor "the heart," little heart; the essence of a seed, and principle of life of the future plant, attached to and contained within the lobes. It consists of two parts, termed by Linnaeus Plumula and Rostellum. The former is the radicula of Grew and other naturalists. The corculum is in fact the embryo of the future vegetable; and is attached by two trunks of vessels to the lobes at their union. The first of its two parts mounts upward, and becomes the trunk. The other strikes into the ground, and is the rudiment of the root. The lobes and heart of the seed are distinctly visible in the bean, and other seeds of that clasps, especially after remaining some time in water or earth.

The principle of life is seated either at the summit or base of the seed. From this circumstance are constructed the two first clasps in Casalpinius's method, containing trees and shrubs only.