vascular plants without seeds
early vascular plants
lycophytes
euphyllophytes
vascular cryptograms
rhyniophytes
zosterophyllophtes
heterospory
trimerophytes
origin of megaphylls
monilophytes
equisetophytes
ferns
upright stems
short cylinders
no leaves
equal dichotomous branching
are homosporous
lateral sporangia
sporangia opened transversely
cones and strobili together
lepidostrobus
lepidophloios
morphology
extant genera
lycopodium
selaginella
isoetes
herbs with prostate rhizomes
true roots and short upright brances
secondary growth never occurs
homosporous
heterosporous
ligules on leaves
heterosporous
microphylls have ligules
small corm like stems with roots
sporophyte is single axis that bears both true roots and megaphyllous leaves
endarch siphonostele
leaf gap