Sexual reproduction in Marchantia - the archegonial head makes the egg cells and, after fertilization with sperm splashed over by the rain from the male part of the plant, the zygote develops into a sporophyte that stays attached underneath the head. The young sporophytes are covered by the white calyptra developing from the wall of the archegonium until the sporangium emerges from its cover. The diploid sporophyte pretty much consists only of a foot (where it is attached to the gametophyte), a short stalk (or seta), and a sporangium which produces spores through meiosis. The rest of the plant is haploid.
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