1. The ovule possesses a very free nucellus with a glandular tip, a single integument adherent to the scale for almost its entire length, a ligule, a large micropyle, and spongy tissue surrounding the gametophyte. 2. There is probably a single functional megaspore, which develops into an embryo sac with about 2000 free nuclei before cell-formation. 3. Cell-formation follows on a peculiar centripetal growth of the cytoplasm and precedes wall-formation. 4. The first walls are formed on the surface of the free cells. 5. Secondary walls are formed on the spindles of the mitoses occurring in the primary cells of the peripheral regions of the gametophyte. 6. The outer cells are uninucleate, the inner ones are multinucleate. 7. The archegonia have single-tiered necks, usually, consisting of about 12 wedge-shaped cells. 8. The necks are on the surface of the prothallus but are often overgrown. 9. The archegonia may be single or occur in complexes and have a single-layered jacket. 10. A ventral canal nucleus may be absent.
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