Not bad for a student project of Nazmi Yaras, Middle East Technical University, Ankara, Turkey. The Palynological Laboratory of the Swedish Museum of Natural History is essentially the birthplace of modern pollen studies. Nice cryptogam site. Both searching and browsing options are available with modest but informative thumbnails. Some 3,000 images from copper-engraved plates are available.
Images are available on thumbnail images that link to half screen jpgs.
This site is provided by the Danish National Library of Science and Medicine. The drawings and paintings, from the eighteenth and nineteenth centuries, are excellent quality and searchable. Links to the abstracts are available. Some of the material is password protected, but what is available for free is impressive. Exams are also available at this site.