Fossilized pollen grains
This fossilized pollen is from a Buckbean fen core found in Yellowstone National Park, Wyoming. The pollen is magnified 1,054 times.
Source
Boundless vets and curates high-quality, openly licensed content from around the Internet. This particular resource used the following sources:
"OpenStax College, Evolution of Seed Plants. November 12, 2013."
http://cnx.org/content/m44653/latest/Figure_26_01_04.jpg
OpenStax CNX
CC BY 3.0.
