Occasional papers of the California Academy of Sciences - California Academy of Sciences (California Academy of Sciences, 1973)

Occasional papers of the California Academy of Sciences - California Academy of Sciences (California Academy of Sciences, 2010)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1906)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1910)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1922)

Offering of mature and seedling orchid plants and orchid seed - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Clarence M. Kilian, 1948)

Official lists and indexes of names and works in zoology. Supplement 1986-2000 - International Commission on Zoological Nomenclature (International Trust for Zoological Nomenclature, c/o Natural History Museum, 2001)

Öfversigt af Finska vetenskaps-societetens förhandlingar - Suomen Tiedeseura (s.n.], 1865)

Öfversigt af Finska vetenskaps-societetens förhandlingar - Suomen Tiedeseura (s.n.], 1866)

Ohio Biological Survey notes - Ohio Biological Survey. (Ohio Biological Survey, 2017)

The Ohio journal of science - Ohio Academy of Science. (Ohio Academy of Science, 1909)

The Ohio journal of science - Ohio Academy of Science. (Ohio Academy of Science, 1919)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1912)

Okens Lehrbuch der Naturgeschichte - Oken, Lorenz, 1779 -1851 (Bei Carl Heinrich Reclam, 1815)

Les Ombellifères : contributions pluridisciplinaires à la systématique : actes du 2e Symposium International sur les Ombellifères, Centre Universitaire de Perpignan, 18-21 mai 1977 - Cauwet-Marc, A.-M. (Anne-Marie) (Missouri Botanical Garden, 1977)

On British wild flowers considered in relation to insects - Lubbock, John, Sir, 1834 -1913 (Macmillan, 1875)

On British wild flowers considered in relation to insects - Lubbock, John, Sir, 1834 -1913 (MacMillan, 1890)

On British wild flowers considered in relation to insects - Lubbock, John, Sir, 1834 -1913 (Macmillan, 1890)

On British wild flowers considered in relation to insects - Lubbock, John, Sir, 1834 -1913 (Macmillan, 1909)

On the history and natural arrangement of insects - Shuckard, William Edward, 1802 -1868 (Printed for Longman, Brown, Green & Longman's Paternoster Row, 1840)

On the history and natural arrangement of insects - Shuckard, William Edward, 1802 -1868 (Printed for Longman, Orme, Brown, Green, & Longmans [etc.], 1840)

One thousand objects for the microscope - Cooke, M. C. (Mordecai Cubitt), 1825 -1914 (F. Warne, 1869)

One thousand objects for the microscope - Cooke, M. C. (Mordecai Cubitt), 1825 -1914 (Frederick Warne, 1869)

Opuscula entomologica - Thomson, C. G. (Carl Gustav), 1824 -1899 (1869)

Opuscula entomologica - Thomson, C. G. (Carl Gustav), 1824 -1899 (1870)

Opuscula entomologica - Thomson, C. G. (Carl Gustav), 1824 -1899 (1888)

The Orchid review (Orchid Review ltd.], 1911)

The Orchid review (Orchid Review ltd.], 1913)

The Orchid review (Orchid Review ltd.], 1921)

Orchidophile; journal des amateurs d'orchideés - Godefroy-Lebeuf, A. (Alexandre), 1844 -1903 (1885)

The orchids of New England. A popular monograph - Baldwin, Henry, 1846 -1911 (J. Wiley & Sons, 1884)

Oregon gladiolus for 1956 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Henry W. Turk Gladiolus, 1956)

Ornithological dictionary of British birds - Rennie, James, 1787 -1867 (Hurst, Chance, 1831)

Ornithological dictionary of British birds - Rennie, James, 1787 -1867 (W. S. Orr & W. Smith, 1833)

Ornithologische Monatsschrift - Deutscher Verein zum Schutze der Vogelwelt. (Kommissions-Verlag der Creutschen Verlagsbuchhandlung, 1908)

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

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1901)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1906)

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

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)

Out of doors : a selection of original articles on practical nautral history - Wood, J. G. (John George), 1827 -1889 (Longmans, Green, 1903)

Outlines of entomology - Murtfeldt, Mary Esther, 1848 -1913 (Tribune printing company, state printers and binders, 1891)

Outlines of entomology - Murtfeldt, Mary Esther, 1848 -1913 (Tribune Printing Company, State Printers and Binders, 1891)

Over de bevruchting der bloemen in het kempisch gedeelte van Vlaanderen - MacLeod, Julius, 1857 -1919 (Vuylsteke, 1894)

P.A. Latreille scientiarum et artium instituti Gallici ... Genera crustaceorum et insectorum : secundum ordinem naturalem in familias disposita, iconibus exemplisque plurimis explicata - Latreille, P. A. (Pierre André), 1762 -1833 (Apud Amand Knig, Bibliopolam, 1807)

P.A. Latreille scientiarum et artium instituti Gallici ... Genera crustaceorum et insectorum : secundum ordinem naturalem in familias disposita, iconibus exemplisque plurimis explicata - Latreille, P. A. (Pierre André), 1762 -1833 (Apud Amand Knig, Bibliopolam, 1809)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1924)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1925)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1927)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1928)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1930)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1931)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1932)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1933)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1936)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1937)