Europeans learned about the wonders of the microscopic world from drawings like this one, created by amateur microscope enthusiast Martin Frobenius Ledermüller in the 1760s. He put bugs, plants, and crystals under the microscope and produced fascinating, highly-symmetrical renderings of what he saw. We've got some etchings much weirder and more alien than this fly below.
I'm not sure what this is, but it looks like something out of Lovecraft.
The results of Ledermüller's work were collected into a three-volume set that would have been the eighteenth century equivalent of coffee table books. All three have recently been put online, and you can browse through them for free. Here are two pictures of plant life. The top one shows seeds sprouting, and the bottom shows mushrooms.
Recreational Microscopy [via BibliOdyssey]