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Jungermanniales (class Hepaticae) An order containing the leafy liverworts. The shoots are usually prostrate or ascending and have a dorsiventral organization. The leaves commonly overlap one another in one of two ways; in the ‘succubous’ arrangement the upper edge of each leaf (i.e. that nearest the shoot apex) is hidden beneath the lower edge of the leaf above; in the ‘incubous’ arrangement the lower edge of each leaf is hidden by the upper edge of the next leaf down. These arrangements are constant characters in genera. Genera include Cephalozia, Diplophyllum, Frullania, Lophocolea, Nardia, Plagiochila, Pleurozia, Porella, and Scapania.