Pacific coast avifauna - Cooper Ornithological Club. (Cooper Ornithological Club, 1914)

Pacific coast avifauna - Cooper Ornithological Club. (Cooper Ornithological Club, 1915)

Pacific coast avifauna - Cooper Ornithological Club. (Cooper Ornithological Club, 1917)

Pacific seabirds : a publication of the Pacific Seabird Group - Pacific Seabird Group. (The Group, 2002)

Pamphlets on forestry in Maryland (1900)

Pamphlets on forestry in West Virginia (1900)

Papers from the Tortugas Laboratory of the Carnegie Institution of Washington - Carnegie Institution of Washington. Department of Marine Biology. (Carnegie Institution of Washington, 1908)

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

Part I. Palæontology - Hall, James, 1811 -1898 (Govt. print. off, 1877)

P.D. Skaar's Montana bird distribution - Bergeron, Dwight. (Montana Natural Heritage Program, 1992)

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 (Houghton Mifflin, 1895)

Pepacton - Burroughs, John, 1837 -1921 (Houghton, Mifflin, 1902)

Pepacton - Burroughs, John, 1837 -1921 (Houghton, Mifflin, 1895)

Pepacton - Burroughs, John, 1837 -1921 (Houghton Mifflin company, 1909)

Pictures of bird life in pen and pencil - Watkins, M. G. (Morgan George),‏ ‎ 1835 - (Cassell, Petter, Galpin, 1882)

Plumas Lassen Study : 2006 annual report - Sierra Nevada Research Center (U.S.) (USDA Forest Service Pacific Southwest Research Station, Sierra Nevada Research Center, 2006)

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

Polychlorinated biphenyl hazards to fish, wildlife, and invertebrates : a synoptic review - U.S. Fish; Wildlife Service (The Service, 1986)

A popular handbook of the birds of Canada and the United States - Nuttall, Thomas, 1786 -1859 (Musson Book Co, 1907)

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, 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 birds of the United States and Canada - Nuttall, Thomas, 1786 -1859 (Little, Brown, 1919)

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)

Popular science news, formerly Boston journal of chemistry. A popular illustrated monthly devoted to the progress in zoology, botany, mineralogy, archaeology, hygiene, invention, with related physical sciences and general scientific information - Agassiz Association. (J.R. Nichols & co. [etc.], 1866)

A popular zoology - Jenks, J. W. P. 1819 -1894 (A.S. Barnes & Company, 1887)

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

Postilla - Peabody Museum of Natural History. (Peabody Museum of Natural History, 1999)

Potential wildlife-highway interactions at select mile-markers along Montana Department of Transportation routes an ArcView GIS analysis - Irby, Lynn R. (Fish and Wildlife Management Program, Montana State University, 2001)

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

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

A preliminary catalog of the birds of Missouri - Widmann, Otto (Academy of Science 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)

Preliminary report of explorations in Nebraska and Dakota, in the years 1855-'56-'57 - Warren, Gouverneur Kemble, 1830 -1882 (Govt. Print. Off, 1875)

Preliminary report of the United States Geological Survey of Wyoming : and portions of contiguous territories, (being a second annual report of progress) - Geological; Geographical Survey of the Territories (U.S.) (Govt. Print. Off, 1872)

A preliminary review of the birds of Nebraska : with synopses - Wolcott, Robert Henry, 1868 -1934 (Klopp & Bartlett Co, 1904)

Principles of economic zoo̤logy - Daugherty, L. S. (Lewis Sylvester) 1857 -1919 (W.B. Saunders, 1915)

Principles of economic zoölogy - Daugherty, L. S. (Lewis Sylvester) 1857 -1919 (W. B. Saunders company, 1912)

Principles of economic zoölogy - Daugherty, L. S. (Lewis Sylvester) 1857 -1919 (W. B. Saunders, 1917)

Principles of economic zoölogy - Daugherty, L. S. (Lewis Sylvester) 1857 -1919 (W.B. Saunders, 1912)

Proceedings - Essex Institute. (1856)

The proceedings and transactions of the Nova Scotian Institute of Science, Halifax, Nova Scotia - Nova Scotian Institute of Science. (Printed for the Institute by W. McNab, 1895)

The Proceedings and transactions of the Nova Scotian Institute of Science - Nova Scotian Institute of Science. (Nova Scotian Institute of Science, 1902)

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

The Proceedings and transactions of the Nova Scotian Institute of Science - Nova Scotian Institute of Science. (Nova Scotian Institute of Science, 1915)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1846)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1852)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1860)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1861)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1866)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1868)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1871)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1875)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1883)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1885)

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, 1903)

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, 1908)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1909)

Proceedings of the American Philosophical Society held at Philadelphia for promoting useful knowledge - American Philosophical Society. (American Philosophical Society, 1899)

Proceedings of the American Philosophical Society held at Philadelphia for promoting useful knowledge - American Philosophical Society. (American Philosophical Society, 1901)

Proceedings of the American Philosophical Society held at Philadelphia for promoting useful knowledge - American Philosophical Society. (American Philosophical Society, 1909)

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

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1851)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1854)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1856)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1859)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1865)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1868)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1871)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1872)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1874)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1875)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1878)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1880)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1884)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1904)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1907)

Proceedings of the California Academy of Sciences - California Academy of Sciences (California Academy of Sciences, 1873)

Proceedings of the California Academy of Sciences - California Academy of Sciences (California Academy of Sciences, 1888)

Proceedings of the California Academy of Sciences - California Academy of Sciences (California Academy of Sciences, 1889)

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, 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 Canadian Institute - Glenny, George, 1793 -1874 (Canadian Institute, 1879)

Proceedings of the Canadian Institute - Glenny, George, 1793 -1874 (Canadian Institute, 1887)

Proceedings of the Canadian Institute - Glenny, George, 1793 -1874 (Canadian Institute, 1890)

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 Delaware County Institute of Science - Delaware County Institute of Science. (The Institute, 1905)

Proceedings of the Essex Institute - Essex Institute. (Essex Institute Press, 1860)

Proceedings of the Essex Institute - Essex Institute. (Essex Institute Press, 1864)

Proceedings of the Essex Institute - Essex Institute. (Essex Institute Press, 1866)

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.], 1904)