The Encyclopedia Americana (1920)/Achene

ACHENE, ACHENIUM, AKENE, a-kēn′, etc. (“not gaping”), a dry, hard, one-seeded fruit in which the wrappings of the seed set closely to it, forming almost a coat. The entire family of Compositæ are of this sort: the “seeds” of borage, the sunflower, thistle, dandelion, etc. Sometimes they are grouped on a common receptacle, called an etærio; as in the strawberry, where it is fleshy, the achenes being the “pits,” or in the centre of the buttercup, where they form the “fruit”; sometimes they are inclosed in the fleshy tube of the calyx, as in the rose.