The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1909)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1906)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1913)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank Haak), 1861 -1937 (Frank H. Lattin, 1898)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank Haak), 1861 -1937 (Frank H. Lattin, 1899)

Opinions and declarations rendered by the International Commission on Zoological Nomenclature - International Commission on Zoological Nomenclature (Printed by order of the International Trust for Zoological Nomenclature, 1958)

Osteology, phylogeny, and higher classification of the fishes of the order Plectognathi (Tetraodontiformes) - United States. National Marine Fisheries Service. (U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, 1980)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1892)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1909)

Our common insects A popular account of the insects of our fields, forests, gardens, and houses - Packard, A. S. (Alpheus Spring), 1839 -1905 (Estes and Lauriat, 1873)

Our native ferns, or, A history of the British species and their varieties / by E.J. Lowe - Lowe, E. J. (Edward Joseph), 1825 -1900 (G. Bell & Sons, 1874)

Our native ferns; or, A history of the British species and their varieties - Lowe, E. J. (Edward Joseph), 1825 -1900 (Groombridge, 1865)

Outlines of vertebrate palæontology for students of zoology - Woodward, Arthur Smith, 1864 -1944 (University Press, 1898)

Palaeontographia Italica : Memorie di paleontologia - Canavari, Mario 1855 -1928 (Tip. T. Nistri, 1895)

Palaeontographia Italica : Memorie di paleontologia - Canavari, Mario 1855 -1928 (Tip. T. Nistri, 1916)

Palaeontographica (Theodor Fischer, 1863)

Palaeontographica (Theodor Fischer, 1876)

Palaeontographica (Theodor Fischer, 1905)

Palaeontographica Americana - Paleontological Research Institution (Ithaca, N.Y.) (Paleontological Research Institution, 1965)

Palaeontology - Palaeontological Association (Palaeontological Association, 1988)

Palæontology of New-York ... - Hall, James, 1811 -1898 (Printed by C. Van Benthuysen, 1847)

Palaeontology; or, A systematic summary of extinct animals and their geological relations - Owen, Richard, 1804 -1892 (A. and C. Black, 1860)

Palæontology; or, A systematic summary of extinct animals and their geological relations - Owen, Richard, 1804 -1892 (A. and C. Black, 1860)

Palaeontology, or, A systematic summary of extinct animals and their geological relations - Owen, Richard, 1804 -1892 (A. and C. Black, 1860)

Palaozoologie : Entwurf einer systematischen Darstellung der Fauna der Vorwelt - Giebel, C. (Christoph), 1820 -1881 (Nulandt'sche buchandlung (L. Garcke), 1846)

Paleontologia del regno di Napoli : contenente la descrizione e figura di tutti gli avanzi organici fossili racchuisi nel suolo di questo regno - Costa, Oronzio Gabriele, 1789 -1867 (Tramater, 1854)

Paleontology of the Eureka district - Walcott, Charles D. (Charles Doolittle), 1850 -1927 (Govt. print. off, 1884)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1881)

Pamphlets on forest protection (1900)

Pamphlets on forestry. Fish and game (1900)

Pamphlets on forestry in Maine (1900)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1959)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1968)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1974)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1986)

Le parasitisme et la symbiose - Caullery, Maurice, 1868 -1958 (Doin, 1922)

Petrifactions and their teachings, or, A hand-book to the gallery of organic remains of the British Museum - British Museum (Natural History). Department of Zoology. (H.G. Bohn, 1851)

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1910)

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1906)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1965)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1981)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1995)

The Plagiostomia : Sharks, skates, and rays / by Samuel Garman ; with seventy-seven plates - Garman, Samuel, 1843 -1927 (Printed for the Museum, 1913)

Plant life - American Plant Life Society. (American Plant Life Society, 1946)

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Plantarum vascularium genera :secundum ordines naturales digesta eorumque differentiae et affinitates tabulis diagnostacis expositae - Weidmann. (Libraria Weidmannia, 1836)

Poissons provenant des campagnes du yacht Princesse-Alice (1901-1910) - Zugmayer, Eric (1911)

The popular encyclopedia; being a general dictionary of arts, sciences, literature, biography, history, and political economy, reprinted from the American edition of the "Conversations lexicon" ... with dissertations on the rise and progress of literature (Blackie, 1900)

Popular greenhouse botany; containing a familiar and technical description of a selection of the exotic plants introduced into the greenhouse - Catlow, Agnes, 1807? -1889 (L. Reeve, 1857)

Popular official guide to the New York Zoological Park - New York Zoological Society. (New York Zoological Society, 1901)

Popular west coast flora; an analytical key to the flora of the Pacific coast, in which are described over eighteen hundred species of flowering plants growing west of the Sierra Nevada and Cascade crests, from San Diego to Puget Sound - Rattan, Volney, 1840 -1915 (The Whitaker & Ray co. (incorporated), 1905)

Postilla - Peabody Museum of Natural History. (Peabody Museum of Natural History, 1950)

A preliminary list of the insects of the province of Quebec part II –Diptera (two-winged flies) - Beaulieu, Germain, 1870 -1944 (s.n, 1915)

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Proceedings and transactions of the Natural History Society of Glasgow - Natural History Society of Glasgow. (The Society, 1883)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1935)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1947)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1950)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1953)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1962)

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

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Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1919)

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 American Academy of Arts and Sciences - American Academy of Arts; Sciences. (Metcalf and Co, 1875)

Proceedings of the American Philosophical Society held at Philadelphia for promoting useful knowledge - American Philosophical Society. (American Philosophical Society, 1869)

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Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1897)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1916)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1917)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1926)

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

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

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

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1949)