Estimated value is over $20,000. This is from The Quadrupeds of North America Imperial Folio series. Bos Americanus, GMEL. American Bison or Buffalo. 1/8 Natural Size. Hand-colored stone lithograph. It's estimated that only 303 sets of the Imperial Folio Quadrupeds were ever completed so this is very rare. The buffalo is the most desirable animal in the series. The lithograph was removed from it's frame to show the actual state of the paper; view photos for several condition issues including tears at the bottom and some toning issues. Note that the top and some of the bottom of the lithograph has been cut at one point in time to fit a frame but the majority of the print is there. The Quadrupeds series was recently featured on Antique's Roadshow (http://www.pbs.org/wgbh/roadshow/archive/201402A46.html).