Close-up of the underside of a leaf of the \male fern\", Dryopteris filix-mas, showing the spore- bearing structures known as sori. The spores are con

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Close-up of the underside of a leaf of the \male fern\", Dryopteris filix-mas, showing the spore- bearing structures known as sori. The spores are contained within the small, black sporangia (spore sacs) which protrude from under the brown, kidney- shaped protective membranes. Some of the sori are coated with a pale grey fungus."

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Size: 3425px × 5226px
Photo credit: © DR MORLEY READ/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: botany, dryopteris, fern, ferns, filix-mas, leaf, male, nature, plant, pteridophyte, pteridophytes, sorus, sporangium