Occasional papers of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1901)

Occasional papers of the California Academy of Sciences - California Academy of Sciences (California Academy of Sciences, 1977)

Oeconomische Naturgeschichte für den deutschen Landmann und die Jugend in den mittleren Schulen - Fabricius, Johann Christian, 1745 -1808 (Bey Friedr. Gotth. Jacobäer und Sohn, 1782)

Oeuvres entomologiques de Eschscholtz. Tome 1, Entomographien - Eschscholtz, Johann Friedrich, 1793 -1831 (Lequien Fils, 1835)

Official lists and indexes of names and works in zoology - International Commission on Zoological Nomenclature (ICZN, 1987)

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 Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1855)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1856)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1895)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1896)

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

Olivier's Entomologie oder Naturgeschichte der Insekten mit ihren Gattungs- und ArtMerkmalen, ihrer Beschreibung und Synonymie. Käfer - Sturm, Jakob, 1771 -1848 (Gedrukkt und im Verlage bei Karl Reichard, 1800)

Om insekter inneslutne i copal : jemte beskrifning på några deribland förekommande nya slagten och arter - Dalman, Johan Wilhelm, 1787 -1828 (Tryckt hos P.A. Norstedt, 1826)

Omphalos: an attempt to untie the geological knot ... - Gosse, Philip Henry, 1810 -1888 (J. Van Voorst, 1857)

On aquatic carnivorous Coleoptera or Dytiscid - Sharp, David, 1840 -1922 (Pub. by the Royal Dublin society, 1882)

On the development and life-histories of the Teleostean food and other fishes - M'Intosh, William Carmichael, 1838 -1931 (R. Grant & Son, 1890)

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)

On the power, wisdom and goodness of God, as manifested in the creation of animals, and in their history, habits and instincts - Kirby, William, 1759 -1850 (Carey, Lea & Blanchard, 1836)

On the senses, instincts, and intelligence of animals, with special reference to insects - Lubbock, John, Sir, 1834 -1913 (K. Paul, Trench, 1889)

On the senses, instincts, and intelligence of animals : with special reference to insects - Lubbock, John, Sir, 1834 -1913 (Kegan Paul, Trench & Co, 1889)

On the senses, instincts, and intelligence of animals, with special reference to insects - Lubbock, John, Sir, 1834 -1913 (D. Appleton and Company, 1888)

On the senses, instincts, and intelligence of animals : with special reference to insects - Lubbock, John, Sir, 1834 -1913 (Kegan Paul, Trench, 1888)

Onomasticon zoicon, plerorumque animalium differentias & nomina propria pluribus linguis exponens : cui accedunt Mantissa anatomica, et quaedam De variis fossilium generibus - Charleton, Walter, 1619 -1707 (Apud Jacobum Allestry ..., 1668)

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)

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, 1956)

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, 1957)

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, 1954)

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, 1939)

Opuscoli scientifici d'entomologia, di fisica e d'agricoltura - Termeyer, Ramón María, 1737 -1814 (Nella Stamperia del Giornale italico di Carlo Dova, contrada S. Rafaello, num. 998, 1807)

The Orchidaceae of Mexico and Guatemala - Bateman, Jas. (James), 1811 -1897 (Ridgway, 1837)

The orders, sub-orders and genera of insects - Couper, William, 1886 (s.n, 1864)

Der Organismus der Infusionsthiere - Stein, Friedrich, 1818 -1885 (W. Engelmann, 1859)

Ornithologisches Jahrbuch (V. Tschusi, 1903)

Orthoptera Helvetiae : analytisch bearbeitet als Grundlage einer Orthopterenfauna der Schweiz - Schoch, Gustav, 1833 -1899 (Druck von F. Rothermel, 1886)

The Orthoptera of Indiana : an illustrated descriptive catalogue of the species known to occur in the state, with bibliography, synonymy and descriptions of new species - Blatchley, W. S. (Willis Stanley), 1859 -1940 ([Indiana Dept. of Geology and Natural Resources, 1903)

The Orthoptera of New England. Designed for the use of the students in the Massachusetts agricultural college and the farmers of the state - Fernald, C. H. (Charles Henry), 1838 -1921 (Wright & Potter printing company, 1888)

Orthoptera of northeastern America, with especial reference to the faunas of Indiana and Florida - Blatchley, W. S. (Willis Stanley), 1859 -1940 (The Nature Publishing Company, 1920)

Orthoptera of northeastern America : with especial reference to the faunas of Indiana and Florida - Blatchley, W. S. (Willis Stanley), 1859 -1940 (Nature Pub. Co., 1920, 1920)

Orthoptères - Burr, Malcolm, 1878 -1954 (1913)

Osservazioni naturali intorno alle cavallette nocive della Campagna Romana / [da Luigi Metaxa e Sebastiano Rolle] - Rolle, Sebastiano, (Vincenzo Poggioli, 1825)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1907)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1908)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1913)

Outlines of comparative anatomy intended principally for the use of students - Fyfe, Andrew, 1754 -1824 (Printed by J. Pillans & Sons for Adam Black ... [etc.], 1818)

Outlines of comparative physiology : touching the structure and development of the races of animals, living and extinct - Agassiz, Louis, 1807 -1873 (H. G. Bohn, 1851)

Outlines of entomology, published in connection with the author's annual reports upon injurious insects. Part first. Including the order of coleoptera - LeBaron, William. (State Journal Steam Print, 1874)

Outlines of general zoology - Baird, Spencer Fullerton, 1823 -1887 (Rudolph Garrigue, 1851)

Outlines of the natural history of Great Britain and Ireland, containing a systematic arrangement and concise description of all the animals, vegetables and fossiles which have hitherto been discovered in these kingdoms - Berkenhout, John, 1730 -1791 (Printed for P. Elmsly (Successor to Mr. Vaillant), 1769)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (H. Frowde and Hodder & Stoughton, 1899)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (Young J. Pentland, 1895)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (D. Appleton & Co, 1895)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (D. Appleton & Co, 1892)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (Appleton, 1916)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (Young J. Pentland, 1892)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (Pentland, 1899)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (D. Appleton, 1895)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (Humphrey Milford, Oxford University Press, 1929)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (D. Appleton, 1906)

Oxford gardens, based upon Daubeny's Popular guide to the physick garden of Oxford: with notes on the gardens of the colleges and on the University park - Gunther, R. T. (Robert Theodore), 1869 -1940 (Parker & son; [etc., etc.], 1912)

Oxford gardens. Based upon Daubeny's Popular guide to the physick garden of Oxford : with notes on the gardens of the colleges and on the University Park - Gunther, R. T. (Robert Theodore), 1869 -1940 (Parker, 1912)

P. Dioscoridae pharmacorum simplicium reiq[ue] medicae libri VIII - Barbaro, Ermolao, 1454 -1493 (Apud Io. Schottum, 1529)

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)

Pacific science - University of Hawaii. (University Press of Hawaii, 1961)

Palaeontographia Italica : Memorie di paleontologia - Canavari, Mario 1855 -1928 (Tip. T. Nistri, 1913)

Palaeontographica (Theodor Fischer, 1846)

Palaeontographica (Theodor Fischer, 1861)

Palaeontographica (Theodor Fischer, 1864)

Palaeontographica (Theodor Fischer, 1866)

Palaeontologie. Beiträge insekten-fauna der vorwelt - Assmann, August. (1870)

Palaeontology; or, A systematic summary of extinct animals and their geological relations - Owen, Richard, 1804 -1892 (A. and C. Black, 1861)

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, 1861)

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

Palaeozoische Arachniden - Frič, Antonín, 1832 -1913 (1904)

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

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1881)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1888)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1914)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1916)

Pamphlets on forest protection (1900)

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, 1962)

Papéis avulsos do Departamento de Zoologia - São Paulo Departamento de Zoologia (A Secretaria, 1947)

Papers and proceedings of the Royal Society of Tasmania - Royal Society of Tasmania. (The Society, 1863)

Papillons d'Europe, peints d'après nature - Devillers, Charles, 1724 -1809 (Chez P.M. Delaguette, imprimeur-libraire, 1785)

Parasites : a treatise on the entozoa of man and animals, including some account of the ectozoa - Cobbold, T. Spencer (Thomas Spencer), 1828 -1886 (J. & A. Churchill, 1879)

Parasites a treatise on the entozoa of man and animals including some account of the ectozoa - Cobbold, T. Spencer (Thomas Spencer), 1828 -1886 (J. & A. Churchill, 1879)

Les parasites des habitations humaines et des denrees alimentaires ou commerciales - Trouessart, E.-L. (Edouard-Louis), 1842 -1927 (G. Masson, 1895)

Parasites : a treatise on the entozoa of man and animals including some account of the ectozoa - Cobbold, T. Spencer (Thomas Spencer), 1828 -1886 (J. & A. Churchill, 1879)

Parasitology - British Society for Parasitology. (Cambridge University Press, 1910)