In article ,
wrote...

David Hershey schreef
The term spicule is applied to the skeletons of sponges:

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According to Harris & Harris it is also used for a small spike in plants, an
outgrowth of the epidermis
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But not for things like these peltate trichomes or scales, of
course.

mel turner schreef
Where did the fern come from? What does it look like?

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Obviously these three pictures are from a directory that showcases pictures
made by Nikon equipment.

Thanks. I missed that [failed to look 'upstream' at

http://mywebpages.comcast.net/nghy/nikon990/

and I also failed to note the original poster's statement that
they were photographed from a prepared microscope slide inexplicably
labelled "fern spicules".

Apparently it of US origin. Beyond that it will be
anybody's guess.

True. But P. polypodioides is a common US fern with such scales
[if the original microscope slide was from a US fern]

cheers