Spore

A single cell. Spores are produced in capsules called sporangia. Most ferns produce 64 spores in each sporangium. Sporangia are aggregated into clusters called sori. When mature, the spores are released from the sporangia. Once released, the spores germinate readily on contact with damp soil.

Image acknowledgement: Australasian Pollen and Spore Atlas, Creative Commons