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Fig. 9.—A spore-bearing leaf )megasporophyll) from a female cycad (Cycas revoluta), bearing six young spore cases (ovules) containing “large” spores (megapores).
The spores have developed, within the spore cases, into the egg-bearing phase of the plant (gametophyte). The spore-bearing phase of the next generation begins its development within the tissues of the egg-bearing phase, thus forming the embryo, which resumes its growth when the seed germinates. The “small” spores (microspores) are borne in microsporophylls on male plants.
Reproduced, by permission, from Gager’s Fundamentals of Botany, published by P. Blakiston’s Sons and Co.
