Fig. 3
From: Ontogenetic characterization of sporangium and spore of Huperzia serrata: an anti-aging disease fern
Morphological changes of sporangium wall from the spore formation through release. a At the stage of mature spore mother cell (MSMC), showing initiation of cell degeneration from tapetum (Ta); b, c disruption of secretory tapetum (ST) in the sporangium wall (SW); d, e the constricting location (CL) from the sporangium wall (SW) of kidney-shaped sporangia; f, g the feature of the sporangium wall (SW) in the stage of uninucleate spores (UNS); h disruption of the sporangium wall (SW)