The branching ofTrichomanes proliferum(Hymenophyllaceae)

摘要

The general morphology, anatomy, and meristem histology ofTrichomanes proliferumwere studied in order to explain the morphogenesis of this fern. As opposed to Bierhorst's conclusions,T.proliferumwas found to be a typical fern with normal tetrahedral shoot apical cells and lenticular leaf apical cells. The leaf is a lateral production of the shoot apical meristem. This species is similar morphologically to other species in the genusTrichomanes: the shoot apical meristems on the creeping stolons produce "lateral systems," composed of a leaf and a bud, which are extraaxillary, as in otherTrichomanesspecies with a creeping filiform stolon. The unique morphology of this fern is due to two supplementary branching systems: a lateral branching of the stolon, which is leafless at the fork, and an epiphyllous budding, which results in the formation of additional leaves by a different process of development.Key words: fern, branching, morphogenesis, histogenesis, epiphyllous buds.