The Morphology of Pteridophytes: The Structure of Ferns and Allied Plants

adaxial aerial axes annulus antheridia antherozoids archegonium axis Bierhorst bracts branch systems canal cell Carboniferous cells thick cm long cone cortex creeping dehiscence described Devonian dichotomous dictyostele division embryo endodermis evolution ferns fertile appendages Filicales fossil frond gametophyte genera genus give rise gymnosperms heterosporous illustrated in Fig indusium internal anatomy internodal Isoetes known lamina large numbers lateral branches leaf bases leaf traces leaves Leclercq Lepidodendrales leptosporangiate Lower Carboniferous Lycopodium Lycopsida Marattiales medullated megasporangium megaspore mesarch metaxylem microspores morphologists occur Ophioglossum organs outer parenchyma petiole phloem pinnae pinnules plant primary wood primitive prothalli prothallus protostele protoxylem Psilotum pteridophytes reconstruction regions represented rhizoids rhizome Rhynia root scalariform secondary wood Selaginella selago similar single solenostele sori sorus species Sphenophyllum spirally arranged sporangia sporangiophores sporangium sporangium wall spores sporocarp sporophylls stages stele stem apex sterile stomata strand structure suspensor terminal thickening tissue Tmesipteris tracheids trunk Upper vascular bundle whorl xylem zygote