Papers and communications read before the Natural History Society of British Columbia - Natural History Society of British Columbia. (Natural History Society of British Columbia?], 1891)

Parasitology - British Society for Parasitology. (Cambridge University Press, 1916)

Pennsylvania bird life; a manual of the birds of Pennsylvania; treating especially of their food, from examinations of several thousand stomachs, made during all seasons of the year, with descriptions of the birds, their nests, eggs and habits - Warren, Benjamin Harry, 1858 -1926 (Penn'a., Pub by the author, 1892)

Pepacton - Burroughs, John, 1837 -1921 (Houghton, Mifflin, 1901)

Pepacton - Burroughs, John, 1837 -1921 (1897)

Petri Artedi renovati pars I. et II. [III-V] : i.e. bibliotheca et philosophia ichthyologica - Linné, Carl von, 1707 -1778 (Impensis A.F. Röse, 1792)

Philippine birds - Du Pont, John E. (John Eleuthère), 1938 -2010 ([Delaware Museum of Natural History], 1971)

Physiology of the temperature of birds - Baldwin, Samuel Prentiss, 1868 -1938 (Cleveland Museum of Natural History, 1932)

Planches coloriees des oiseaux de la Belgique et de leurs oeufs - Dubois, Ch. F. (Charles Frédéric), 1804 -1867 (C. Muquardt, 1854)

Pocket guide to the common land birds of New England - Willcox, M. A. (Mary Alice), 1856 -1953 (Lee and Shepard, 1895)

Pocket key of the birds of the northern United States, east of the Rocky Mountains - Apgar, A. C. (Austin Craig), 1838 -1908 (J.L. Murphy Pub. Co., Printers, 1893)

A popular handbook of the birds of Canada and the United States - Nuttall, Thomas, 1786 -1859 (Musson Book Co, 1903)

A popular handbook of the birds of the United States and Canada - Nuttall, Thomas, 1786 -1859 (Little, Brown, 1905)

A popular handbook of the birds of the United States and Canada - Nuttall, Thomas, 1786 -1859 (Little, Brown, 1921)

A popular handbook of the ornithology of eastern North America - Nuttall, Thomas, 1786 -1859 (Little, Brown, 1891)

A popular Handbook of the Ornithology of Eastern North America - Nuttall, Thomas, 1786 -1859 (Truslove and Hanson, 1894)

A popular handbook of the ornithology of eastern North America - Nuttall, Thomas, 1786 -1859 (Little, Brown, and Company, 1896)

A popular handbook of the ornithology of the United States and Canada, based on Nuttall's Manual - Nuttall, Thomas, 1786 -1859 (Little, Brown, and Company, 1891)

Portraits and habits of our birds - Pearson, T. Gilbert (Thomas Gilbert), 1873 -1943 (National association of Audubon societies, 1921)

Portraits and habits of our birds - Pearson, T. Gilbert (Thomas Gilbert), 1873 -1943 (National Association of Audubon Societies, 1925)

A practical handbook of British birds - Witherby, H. F. (Harry Forbes), 1873 -1944 (Witherby, 1924)

A practical handbook of British birds - Witherby, H. F. (Harry Forbes), 1873 -1944 (Witherby, 1920)

A preliminary catalog of the birds of Missouri - Widmann, Otto (Academy of Science of St. Louis, 1907)

A preliminary catalog of the birds of Missouri - Widmann, Otto (Academy of Sciences of St. Louis?, 1907)

A preliminary list of the birds found in Vermont - Perkins, George H. (George Henry), 1844 -1933 (Wynkoop Hallenbeck Crawford Co, 1901)

A preliminary list of the birds of Wayne County, Ohio - Oberholser, Harry C. (Harry Church), 1870 -1963 (Westbote Co., State Printers, 1896)

A preliminary report on the biology of Harding County, northwestern South Dakota - Visher, Stephen Sargent, 1887 -1967 (State Publishing Co, 1914)

Proceedings - Dorset Natural History; Archaeological Society.

Proceedings and transactions of the Nova Scotian Institute of Natural Science - Nova Scotian Institute of Natural Science. (Nova Scotian Institute of Natural Science, 1886)

Proceedings - Dorset Natural History and Archaeological Society - Dorset Natural History; Archaeological Society. (1877)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1889)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1890)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1892)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1893)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1895)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1896)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1898)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1899)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1904)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1905)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1913)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1841)

Proceedings of the American Philosophical Society held at Philadelphia for promoting useful knowledge - American Philosophical Society. (American Philosophical Society, 1900)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1908)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1911)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1914)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1921)

Proceedings of the Bournemouth Natural Science Society - Bournemouth Natural Science Society (1929)

Proceedings of the Bournemouth Natural Science Society - Bournemouth Natural Science Society (1936)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1939)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1944)

Proceedings of the California Academy of Sciences - California Academy of Sciences (California Academy of Sciences, 1896)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1919)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1923)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1924)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1926)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1927)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1929)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1931)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1935)

Proceedings of the Davenport Academy of Natural Sciences - Davenport Academy of Natural Sciences. (Academy of Natural Sciences [etc.], 1885)

Proceedings of the Davenport Academy of Natural Sciences - Davenport Academy of Natural Sciences. (Academy of Natural Sciences [etc.], 1910)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1955)

Proceedings of the Indiana Academy of Science - Indiana Academy of Science. ([s.n.], 1895)

Proceedings of the Indiana Academy of Science - Indiana Academy of Science. ([s.n.], 1902)

Proceedings of the Indiana Academy of Science - Indiana Academy of Science. ([s.n.], 1904)

Proceedings of the Indiana Academy of Science - Indiana Academy of Science. ([s.n.], 1920)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1891)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1929)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1951)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1960)

Proceedings of the Linnaean Society of New York ... - Linnaean Society of New York (Linnaean Society of New York, 1933)

Proceedings of the Manchester Institute of Arts and Sciences - Manchester Institute of Arts; Sciences. (The Institute, 1900)

Proceedings of the Nebraska Ornithologists' Union - Nebraska Ornithologists' Union at its ... meeting. (1908)

Proceedings of the New England Zoölogical Club - New England Zoological Club. (The Club, 1903)

Proceedings of the Ornithological Sub-section of the Biological Section of the Canadian Institute - Royal Canadian Institute. Biological Section. Ornithological Sub-section. (The Institute, 1890)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1880)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1886)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1887)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1889)