A preliminary list of the vascular flora of Allegheny County, Pennsylvania - Shafer, John Adolph, 1863 -1918 (Carnegie Institute Museum?, 1901)

A preliminary list of the vascular plants of the Lackawanna and Wyoming valleys - Dudley, William Russel, 1849 -1911 (The Republican Press, 1887)

Preservation of natural features and scenic views in New York City - Clarke & Rapuano. (The Department, 1974)

President's Address, Papers & Reports / West Kent Natural History, Microscopical & Photographic Society - West Kent Natural History Microscopical; Photographic Society. (1872)

Price list, 1932 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Wild Flowers (Inc.), 1932)

Price list : fall 1928 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (L.E. Williams Nursery Co, 1928)

Price list for fall 1952 : hardy ferns, wild flowers, bulbs and native orchids - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Johnson's Nurseries, 1952)

Price list of hardy plants, shrubs, vines and aquatics : for the trade only - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Bellevue Nursery, 1892)

Price-list of native ferns, wild flowers : 1913 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Irving Holcomb, 1913)

Price-list of native ferns, wild flowers : 1921 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Irving Holcomb, 1921)

Price list of native ferns, wild flowers : 1924 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Irving Holcomb, 1924)

Price-list of native ferns, wild flowers : 1924[-7] - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Irving Holcomb, 1927)

Price-list of native ferns, wild flowers : 1928 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Irving Holcomb, 1928)

Price list of seeds of American conifers, trees, shrubs, herbs. No. 22, 1914-1915 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Otto Katzenstein & Company, 1914)

Price list of seeds of American conifers, trees, shrubs, herbs. No. 24, 1916-17 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Otto Katzenstein & Company, 1916)

Price list of seeds of conifers, forest and ornamental trees, shrubs, palms, fruit trees and roots and seeds of medicinal plants. No. 48, season 1928-1929 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Otto Katzenstein & Co, 1928)

Price list of seeds of conifers, forest and ornamental trees, shrubs, palms, fruit trees and roots and seeds of medicinal plants. No. 46, season 1927-1928 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Otto Katzenstein & Co, 1927)

Price list of seeds of conifers, forest and ornamental trees, shrubs, palms, fruit trees and roots and seeds of medicinal plants. No. 44, season 1926-1927 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Otto Katzenstein & Co, 1926)

Price list of seeds of conifers, forest and ornamental trees, shrubs, palms, fruit trees and roots and seeds of medicinal plants. No. 50, season 1929-1930 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Otto Katzenstein & Co, 1929)

The primeval forest types of southwestern New York - Gordon, Robert B. (Robert Benson), 1901 -1981 (University of the State of New York, 1940)

Prince catalogue - Wm. R. Prince & Co. (Wm. R. Prince & Co)

Prince's annual catalogue of fruit and ornamental trees and plants : cultivated and for sale at the Linnaean Botanic Garden & Nurseries, Flushing, Long Island, near New-York. All orders are to be addressed only to Wm. R. Prince & Co. only, no other resident of Flushing being authorized to receive any orders whatever for this establishment - Wm. R. Prince & Co. (Wm. R. Prince & Co, 1841)

The principles of biology, by J. I. Hamaker - Hamaker, John Irvin, 1869 - (P. Blakiston, 1913)

The principles of biology - Hamaker, J. I. (John Irvin), 1869 - (P. Blakiston's Sons & Co, 1913)

Principles of botany - Bergen, Joseph Y. (Joseph Young), 1851 -1917 (Ginn, 1906)

The principles of botany : as exemplified in the phanerogamia - Coultas, Harland, 1817 -1877 (King & Baird, printers, 1854)

The principles of botany, as exemplified in the phanerogamia - Coultas, Harland, 1817 -1877 (King & Baird, 1854)

Principles of botany - Bergen, Joseph Y. (Joseph Young), 1851 -1917 (Ginn & company, 1906)

Principles of botany - Bergen, Joseph Y. (Joseph Young), 1851 -1917 (Ginn & Company, 1906)

Proceedings - Nova Scotian Institute of Science. (1866)

Proceedings - Entomological Society of Canada (1863-1871) (Entomological Society of Ontario, 1900)

Proceedings (and Annual Report) of the Holmesdale Natural History Club, Reigate - Holmesdale Natural History Club. (1865)

Proceedings and Transactions of the Croydon Microscopical & Natural History Club - Croydon Microscopical; Natural History Club. (1881)

Proceedings and transactions of the Natural History Society of Glasgow - Natural History Society of Glasgow. (The Society, 1886)

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, 1890)

The Proceedings and transactions of the Nova Scotian Institute of Science - Nova Scotian Institute of Science. (Nova Scotian Institute of Science, 1894)

The Proceedings and transactions of the Nova Scotian Institute of Science - Nova Scotian Institute of Science. (Nova Scotian Institute of Science, 1898)

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, 1883)

Proceedings and transactions of the Royal Society of Canada. Délibérations et mémoires de la Société royale du Canada - Royal Society of Canada. (Société royale du Canada, 1888)

Proceedings and transactions of the Royal Society of Canada. Délibérations et mémoires de la Société royale du Canada - Royal Society of Canada. (Société royale du Canada, 1897)

Proceedings and transactions of the Royal Society of Canada. Délibérations et mémoires de la Société royale du Canada - Royal Society of Canada. (Société royale du Canada, 1900)

Proceedings and transactions of the Royal Society of Canada. Délibérations et mémoires de la Société royale du Canada - Royal Society of Canada. (Société royale du Canada, 1901)

Proceedings and transactions of the Royal Society of Canada. Délibérations et mémoires de la Société royale du Canada - Royal Society of Canada. (Société royale du Canada, 1902)

Proceedings and transactions of the Royal Society of Canada. Délibérations et mémoires de la Société royale du Canada - Royal Society of Canada. (Société royale du Canada, 1903)

Proceedings and transactions of the Royal Society of Canada. Délibérations et mémoires de la Société royale du Canada - Royal Society of Canada. (Société royale du Canada, 1905)

Proceedings and transactions of the Royal Society of Canada. Délibérations et mémoires de la Société royale du Canada - Royal Society of Canada. (Société royale du Canada, 1908)

Proceedings and transactions of the Royal Society of Canada. Délibérations et mémoires de la Société royale du Canada - Royal Society of Canada. (Société royale du Canada, 1910)

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, 1888)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1920)

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, 1889)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1886)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1884)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1892)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1919)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1930)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1932)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1987)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1992)

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, 1864)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1921)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1923)

Proceedings of the Botanical Society of the British Isles - Botanical Society of the British Isles. (1960)

Proceedings of the Botanical Society of the British Isles - Botanical Society of the British Isles. (1963)

Proceedings of the Botanical Society of the British Isles - Botanical Society of the British Isles. (1967)

Proceedings of the Botanical Society of the British Isles - Botanical Society of the British Isles. (1956)

Proceedings of the California Academy of Sciences - California Academy of Sciences (California Academy of Sciences, 1875)

Proceedings of the Canadian Institute - Glenny, George, 1793 -1874 (Canadian Institute, 1883)

Proceedings of the Davenport Academy of Natural Sciences - Davenport Academy of Natural Sciences. (Academy of Natural Sciences [etc.], 1867)

Proceedings of the Davenport Academy of Natural Sciences - Davenport Academy of Natural Sciences. (Academy of Natural Sciences [etc.], 1876)

Proceedings of the Davenport Academy of Natural Sciences - Davenport Academy of Natural Sciences. (Academy of Natural Sciences [etc.], 1901)

Proceedings of the Entomological Society of Ontario - Entomological Society of Ontario. (Entomological Society of Ontario, 1956)

Proceedings of the Entomological Society of Ontario - Entomological Society of Ontario. (Entomological Society of Ontario, 1969)

Proceedings of the Entomological Society of Ontario - Entomological Society of Ontario. (Entomological Society of Ontario, 1987)

Proceedings of the Entomological Society of Ontario - Entomological Society of Ontario. (Entomological Society of Ontario, 1996)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1919)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1945)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1947)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1964)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1988)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1996)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 2002)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 2003)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 2006)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 2007)

Proceedings of the Essex Institute - Essex Institute. (Essex Institute Press, 1848)

Proceedings of the Essex Institute - Essex Institute. (Essex Institute Press, 1856)

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

Proceedings of the Florida Academy of Sciences - Florida Academy of Sciences. (Rose Printing Co., etc, 1936)

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.], 1901)

Proceedings of the Indiana Academy of Science - Indiana Academy of Science. ([s.n.], 1900)

Proceedings of the Indiana Academy of Science - Indiana Academy of Science. ([s.n.], 1905)

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.], 1922)

The Proceedings of the Iowa Academy of Science - Iowa Academy of Science (The Academy, 1907)

Proceedings of the Linnean Society of London - Linnean Society of London. (Published for the Linnean Society of London by Academic Press [etc.], 1838)

Proceedings of the Literary and Philosophical Society of Manchester - Literary; Philosophical Society of Manchester. (The Society, 1873)

Proceedings of the Literary and Philosophical Society of Manchester - Literary; Philosophical Society of Manchester. (The Society, 1875)

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

Proceedings of the Natural History Society of Wisconsin - Wisconsin Natural History Society. (Wisconsin Natural History Society, 1885)

Proceedings of the Nova Scotian Institute of Science - Nova Scotian Institute of Science. (Nova Scotian Institute of Science, 1969)

Proceedings of the Nova Scotian Institute of Science - Nova Scotian Institute of Science. (Nova Scotian Institute of Science, 1982)

Proceedings of the Nova Scotian Institute of Science - Nova Scotian Institute of Science. (Nova Scotian Institute of Science, 1983)