6 books
Probable Causes of Polygamy Among Birds (Classic Reprint)
Nature Books, Popular and Scientific; From the Stock of the Franklin Bookshop
The Mammals of Pennsylvania and New Jersey. a Biographic, Historic and Descriptive Account of the Furred Animals of Land and Sea, Both Living and Extinct, Known to Have Existed in These States ..
Botanica Neglecta. William Young, Jr. (of Philadelphia) Botaniste de Pensylvanie and His Long-Forgotten Book; Being a Facsimile Reprint of His Catalogue D'Arbres Arbustes Et Plantes Herbacees D'Amerique Pub. in Paris in 1783
The Birds Observed in British Columbia and Washington; During Spring and Summer, 1892
The Mammals of Pennsylvania and New Jersey