This thread gives rise to a spiral ciliated band lying in a depression on the body of each spermatozoid; the large spermatozoids eventually escape from the pollen-tube, and are able to perform ciliary movements in the watery liquid which occurs between the thin papery remnant of nucellar tissue and the archegonial necks.
The half of the embryo directed towards the archegonial neck gives rise to the apex of the stem and a sheath of three leaves, the, other half to the small foot and the primary root.
The most important difference in the sexual organs concerns the length of the archegonial neck; this is shortest and has only a single canal cell in L.
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