What is (a) The rudimentary stem of a plant which supports the cotyledons in the seed, and from which the root is developed downward; the stem of the embryo; the caulicle. (b) A rootlet; a radicel called?

radicle — (a) The rudimentary stem of a plant which supports the cotyledons in the seed, and from which the root is developed downward; the stem of the embryo; the caulicle. (b) A rootlet; a radicel. (Webster's 1913.)

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