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

Our early wild flowers : a study of the herbaceous plants blooming in early spring in the northern states - Keeler, Harriet L. (Harriet Louise), 1846 -1921 (Scribner, 1916)

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

Outlines of classification and special morphology of plants - Balfour, Isaac Bayley, 1853 -1922 (Clarendon Press, 1887)

Outlines of classification and special morphology of plants - Goebel, K. (Karl), 1855 -1932 (Clarendon Press, 1887)

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, 1967)

Pacific States Floral Congress. [Papers] - California State Floral Society. (Academy of sciences, 1901)

Palaeontology - Palaeontological Association (Palaeontological Association, 1960)

Paleobotany and biogeography : a festschrift for Alan Graham in his 80th year - Raven, Peter H (Missouri Botanical Garden, 2014)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1886)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1887)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1888)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1891)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1892)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1895)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1904)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1916)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1917)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1918)

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

Pamphlets on forestry. Grazing (1900)

Pamphlets on silviculture (1899)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1969)

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, 1974)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1979)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1981)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1988)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1993)

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

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1997)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1998)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 2002)

Papers presented at the Celebration of the Twentieth Anniversary of the New York Botanical Garden, September 6-9, 1915. Published by the aid of the David Lydig Fund, bequethed by Charles P. Daly - New York Botanical Garden (1916)

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)

Peace parkland native grassland stewardship program 2001/02 - Alberta. Fish; Wildlife Division. (Alberta Sustainable Resource Development, Fish & Wildlife Division, Resource Data and Species At Risk Section, 2004)

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 : Tapiche-Blanco - Field Museum of Natural History. (The Field Museum, 2015)

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

Pflanzen-geographie auf physiologischer Grundlage - Schimper, A. F. W. (Andreas Franz Wilhelm), 1856 -1901 (Gustav Fischer, 1908)

Die pflanzen-mischlinge : ein beitrag zur biologie der gewächse - Focke, Wilhelm Olbers, 1834 -1922 (Gebrüder Borntrager, 1881)

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

Die Pflanzenfeinde aus der Klasse der Insekten. Ein nach Pflanzenfamilien geordnetes Handbuch sämmtlicher auf den einheimischen Pflanzen bisher beobachteten Insekten zum Gebrauch für Entomologen, Insektensammler, Botaniker, Land- und Forstwirthe und Gartenfreunde - Kaltenbach, J. H. (Johann Heinrich), 1807 -1876 (J. Hoffmann, 1874)

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

Das Pflanzenreich :regni vegetablilis conspectus - Engler, Adolf, 1844 -1930 (W. Engelmann, 1907)

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 Pflanzenstoffe in chemischer, physiologischer, pharmakologischer und toxikologischer Hinsicht : für Aerzte, Apotheker, Chemiker und Pharmakologen - Husemann, August, 1833 -1877 (Springer, 1882)

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 - Warburg, Otto, 1859 -1938 (Bibliographisches Institut, 1913)

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 Dalmatiens - Adamović, Lujo (Lujo V.), 1869 -1935 (W. Klinkhardt, 1911)

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)

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

Pharmaceutical botany - Youngken, Heber W. (Heber Wilkinson), 1885 -1963 (P. Blakiston's Son & Co, 1918)

Pharmaceutical botany; a text-book for students of pharmacy and science - Youngken, Heber W. (Heber Wilkinson), 1885 -1963 (P. Blakiston's son & co, 1920)

Pharmaceutical botany, with glossary of botanical terms - Youngken, Heber W. (Heber Wilkinson), 1885 -1963 (Blakiston, 1921)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain. (J. & A. Churchill, 1882)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain (J. & A. Churchill, 1864)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain (J. & A. Churchill, 1867)

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, 1873)

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

Pharmacographia :A history of the principal drugs of vegetable origin, met with in Great Britain and British India - Flückiger, Friedrich A. (Friedrich August), 1828 -1894 (Macmillan and co, 1879)

Pharmacographia indica :A history of the principal drugs of vegetable origin, met with in British India - Dymock, William, 1834 -1892 (K. Paul, Trench, Trübner & co., ld; [etc. etc.], 1893)

The pharmacopoeia of a botanical physician later - Riddell, William Renwick, 1852 -1945 (Botanical Society of Edinburgh?, 1915)