plumule

These plumules interlock and trap tiny pockets of air — it’s actually this layer of air that keeps the cold out and the warmth in.

Embryo thick and fleshy, "with a large concealed cavity at the summit, the plumule curved in a groove on the outside."

The sprout at the end of a seed when it begins to germinate; the plumule in germination; Ð so called from its spiral form.

Finally the plumule escapes, its leaves successively breaking through at the tip of the germ-sheath.

Within the cotyledons the primordial leaves are seen, constituting the plumule or first bud of the plant.