Illustrations of various strains of pollen in extreme magnification, as featured in Ueber den Pollen (1837), a book by St. Petersburg based German pharmacist and chemist Carl Julius Fritzsche.
For a key identifying each pollen type pictured see these descriptions (in German)
|Housed at: Internet Archive
From: University of Illinois Urbana-Champaign via Biodiversity Heritage Library
|Underlying Work: PD Worldwide | Digital Copy: No Additional Rights|
|Download: Right click on image or see source for higher res versions|
The Dartmouth Electron Microscope Facility at Dartmouth College produced this photograph showing pollen strains at similar magnifications to those shown in Fritzsche’s book (around 500 times magnification).