proembryo

Pro*em"bry*o, n. Etym: [Pref. pro- + embryo. ] (Bot.) (a) The series of cells formed in the ovule of a flowering plant after fertilization, but before the formation of the embryo. (b) The primary growth from the spore in certain cryptogamous plants; as, the proembryo, or protonema, of mosses.

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