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Two years and one year pass from ovule initiation to appearance of developed embryos in both Ceratozamia mexicana and Zamia furfuracea respectively. The two species are from contrasting environments, but gametophyte development is similar, though differing in speed. C. J. Chamberlain sustained that the transference of nutrients from the jacket to the central cell occurs through cytoplasmic projections from the central cell. We confirm and describe these connections for the two species using the Schiffâ€™s reaction, staining the cell wall of the central cell. The connections occur between the central cell and the transfer cells that make up the archegonial jacket, through pits in the central cell wall. Cytoplasmic projections measure an average of 7 Î¼m and transverse the cell wall through pits measuring 7.5 Î¼m and 10.5 Î¼m in diameter for Ceratozamia and Zamia respectively. The central cells and transfer cells of both species are described in detail.
Keywords: archegonium, central cell, transfer cell, seed