Here is one of my favorite pictures from the Folger Shakespeare Library.
|Woodcut in Edward Topsell, Historie of Serpents. London, 1608|
Or how about some roses from the University of North Carolina Libraries?
Floral catalogue of Pomona Hill Nurseries, Pomona, N.C. : J. Van Lindley, proprietor : roses, chrysanthemums and other green-house plant, 1889
A complete list of participating libraries can be found here on the Library Journal website.