Oesterreichische botanische Zeitschrift (A. Skofitz, 1905)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1906)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1908)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1909)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1913)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1915)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1919)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1920)

Öfversigt af Finska vetenskaps-societetens förhandlingar - Suomen Tiedeseura (s.n.], 1905)

Ohio Biological Survey notes - Ohio Biological Survey. (Ohio Biological Survey, 2015)

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, 1912)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1910)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1911)

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

On molecular and microscopic science - Somerville, Mary, 1780 -1872 (J. Murray, 1869)

On the elaioplasts in mono- and dicotyledonous plants. –On special cellular bodies which form Anthocyanine. –On a special cellular body found in two orchids - Politis, Ioannes. (1914)

On the fauna and flora of the west of Scotland. Meeting at Glasgow, September, 1876 - British Association for the Advancement of Science. (Blackie, 1876)

The onion (ICAR-Directorate of Knowledge Management in Agriculture, Indian Council of Agricultural Research, 2015)

Onze flora. Beschrijving van de familiën, voornamste geslachten en soorten der in Nederland in het wild groeiende, verwilderde, verbouwde en aangeplante gewassen, alsmede van eenige fraaie en nuttige midden-europeesche planten - Hoffmann, Carl, 1802 -1883 (W.J. Thieme, 1900)

Opmerkingen over eene Buitenzorgsche Kritiek op mijne Exkursionsflora von Java : verweerschrift, op last van den Hoofdinspecteur-Chef van den Dienst van het Boschwezen van Nederlandsch-Indië - Koorders, Sijfert Hendrik, 1863 -1919 (G. Kolff, 1914)

The Orchadian - Australasian Native Orchid Society (The Society, 1991)

The Orchid review (Orchid Review ltd.], 1914)

Orchis :Monatsschrift der Deutschen Gesellschaft für Orchideenkunde - Dammer, Udo. (1910)

The organic constituents of higher plants: their chemistry and interrelationships - Robinson, Trevor. (Burgess Pub. Co, 1963)

The origin of species - Darwin, Charles, 1809 -1882 (Books, Inc, 1900)

The origin of species by means of natural selection, or, The preservation of favoured races in the struggle for life - Darwin, Charles, 1809 -1882 (J. Murray, 1902)

The origin of species by means of natural selection, or, The preservation of favored races in the struggle for life - Darwin, Charles, 1809 -1882 (D. Appleton, 1899)

The origin of species by means of natural selection, or, The preservation of favored races in the struggle for life - Darwin, Charles, 1809 -1882 (A.L. Burt, 1899)

The origin of species by means of natural selection : or The preservation of favored races in the struggle for life - Darwin, Charles, 1809 -1882 (Hurst, 1872)

Origin of species by means of natural selection, or the preservation of favored races in the struggle for life - Darwin, Charles, 1809 -1882 (P. F. Collier, 1905)

Florist's journal (How and Parsons, 1842)

Florist's journal (How and Parsons, 1846)

Ornamental plant explorations, Japan, 1961 - United States. Agricultural Research Service. (Agricultural Research Service, U.S. Dept. of Agriculture in cooperation with Longwood Gardens of the Longwood Foundation, Inc, 1966)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1910)

Our 25th anniversary, 1917-1942 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (William M. Hunt & Co, 1942)

Our South African flora = Ons Suid-Afrikaanse plantegroei - Compton, R. H. (Cape Times, 1900)

Out-of-the-ordinary bulbs for 1958 : 31 years of catering to the bulb collector - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oakhurst Gardens, 1959)

An outline of plant geography (The Macmillan company, 1926)

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)

Pacific science - University of Hawaii. (University Press of Hawaii, 1947)

Pacific science - University of Hawaii. (University Press of Hawaii, 1951)

Pacific science - University of Hawaii. (University Press of Hawaii, 1953)

Pacific science - University of Hawaii. (University Press of Hawaii, 1959)

Pacific science - University of Hawaii. (University Press of Hawaii, 1960)

Pacific science - University of Hawaii. (University Press of Hawaii, 1967)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1892)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1917)

[Pamphlets on agriculture in Guam] (s.n, 1905)

Pamphlets on silviculture (1899)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1972)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1995)

Pandanacées Amaryllidacées - Huynh, Kim-Lang (1986)

Part I. The living flora of West Virginia - Millspaugh, Charles Frederick, 1854 -1923 (Wheeling news litho. co, 1913)

Parthenogenesis und Apogamie im Pflanzenreiche - Winkler, Hans, 1877 - (G. Fischer, 1908)

Partnerships for sustainable forest ecosystem management : fifth Mexico/U.S. biennial symposium : October 17-20, 1994, Guadalajara, Jalisco, Mexico - Rocky Mountain Forest; Range Experiment Station (Fort Collins, Colo.) (U.S. Dept. of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station, 1995)

Perfection seeds, bulbs, plants and garden requisites for 1921 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (William M. Hunt & Company, 1921)

Perú: Cordillera Escalera-Loreto - Stotz, Douglas F. (Douglas Forrester), 1956 - (The Field Museum, Science and Education, 2014)

Peru : Ere-Campuya-Algodón - Field Museum of Natural History. (The Field Museum, Science and Education, 2013)

Peru : Maijuna - Alverson, William Surprison (Field Museum, Environment, Culture and Conservation, 2010)

Perú : Cerros de Kampankis - Stotz, Douglas F. (Douglas Forrester), 1956 - (The Field Museum, Environment, Culture, and Conservation, 2012)

Perú, Medio Putumayo-Algodón - Stotz, Douglas F. (Douglas Forrester), 1956 - (Field Museum of Natural History, 2016)

Perú : Nanay-Mazán-Arabela - Alverson, William Surprison (Field Museum, Environmental and Conservation Programs, 2007)

Perú : Yaguas-Cotuhé - Field Museum of Natural History. (Field Museum, Environment, Culture, and Conservation, 2011)

Pesticides documentation bulletin - National Agricultural Library (U.S.) (National Agricultural Library, U.S. Dept. of Agriculture, #c 1965-1969, 1965)

Pflanzen-Atlas nach dem Linné'schen System - Hoffmann, Carl, 1802 -1883 (Jul. Hoffmann, 1881)

Pflanzen-teratologie systematisch geordnet - Penzig, O. (Ottone), 1856 -1929 (A. Ciminago, 1894)

Pflanzenmikrochemie : ein Hilfsbuch beim mikrochemischen Studium pflanzlicher Objekte - Tunmann, Otto, 1867 -1919 (Gebrüder Borntraeger, 1913)

Pflanzenphysiologie. Versuche und beobachtungen an höheren und niederen pflanzen einschliesslich bakteriologie und hydrobiologie mit planktonkunde - Kolkwitz, R. (Richard), 1873 -1956 (G. Fischer, 1914)

Das Pflanzenreich :regni vegetablilis conspectus - Engler, Adolf, 1844 -1930 (W. Engelmann, 1900)

Die Pflanzenstoffe, botanisch-systematisch bearbeitet ; chemische Bestandteile und Zusammensetzung der einzelnen Pflanzenarten, Rohstoffe und Produkte. Phanerogamen - Wehmer, C. (Carl), 1858 -1935 (G. Fischer, 1911)

Die Pflanzenvereine der Magellansländer : nebst einem Beitrage zur Ökologie der magellanischen Vegetation - Dusén, P. (Per), 1855 -1926 (Kungl. boktr. P.A. Norstedt, 1903)

Die Pflanzenwelt Afrikas, insbesondere seiner tropischen Gebiete : Grundzge der Pflanzenverbreitung im Afrika und die Charakterpflanzen Afrikas - Engler, Adolf, 1844 -1930 (W. Engelman, 1910)

Die Pflanzenwelt der peruanischen Anden in ihren Grundzügen dargestellt - Weberbauer, A. (August), 1871 -1948 (W. Engelmann, 1911)

Die Pflanzenwelt Ost-Afrikas und der Nachbargebiete - Engler, Adolf, 1844 -1930 (D. Reimer, 1895)

Die Pflanzenwelt von West-Australien südlich des Wendekreises. Mit einer Einleitung über die Pflanzenwelt Gesamt-Australiens in Grundzügen. Ergebnisse einer im Auftrag der Humboldt-Stiftung der Kgl. Preussischen Akademie der Wissenschaften, 1900-1902 unternommenen Reise - Diels, Ludwig, 1874 -1945 (W. Engelmann, 1906)

Phanerogamic flora of the divisions of Uitenhage and Port Elizabeth : with a sketch map - Schönland, S. 1860 - (Govt. Print. and Stationery Office, 1919)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain. (J. & A. Churchill, 1876)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain (J. & A. Churchill, 1866)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain. (J. & A. Churchill, 1880)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain. (J. & A. Churchill, 1878)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain. (J. & A. Churchill, 1881)

Philadelphia flower show - Pennsylvania Horticultural Society. (The Society, 1992)

Philadelphia flower show - Pennsylvania Horticultural Society. (The Society, 1993)

Philippine fiber plants - Brown, William Henry, 1884 -1939 (Bureau of Printing, 1919)

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

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, 1911)

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1912)

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1914)

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1919)

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1920)

Philosophical transactions of the Royal Society of London - Royal Society (Great Britain) (Royal Society of London, 1883)

PHS news - Pennsylvania Horticultural Society. (The Society, 1965)

PHS news - Pennsylvania Horticultural Society. (The Society, 1992)

Physical and biological factors affecting the maintenance and management of the giant (saguaro) cactus, Cereus giganteus, Englem [i.e. Engelm] - United States. Bureau of Land Management. (The Bureau, 1972)

Physiological plant anatomy - Haberlandt, Gottlieb, 1854 -1945 (Macmillan and Co, 1914)

Physiological plant anatomy - Haberlandt, Gottlieb, 1854 -1945 (MacMillan, 1914)

Physiology at the farm in aid of rearing and feeding the live stock - Seller, William, 1798 -1869 (W. Blackwood and sons, 1867)

Physis - Sociedad Argentina de Ciencias Naturales. (Asociación Argentina de Ciencias Naturales [etc.], 1921)

Phytogeographic survey of North America. A consideration of the phytogeography of the North American continent, including Mexico, Central America and the West Indies, together with the evolution of North American plant distribution - Harshberger, John W. (John William), 1869 -1929 (W. Engelmann, 1911)