Phycologia mediterranea - Ardissone, Francesco, 1837 -1910 (Antica tip. ferri di Maj e Malnati, 1883)

Phykologie, oder, Einleitung ins Studium der Algen - Montagne, Jean François Camille, 1784 -1866 (C. Graeger, 1851)

Phykologie; oder, Einleitung ius Studium der Algen - Müller, Karl, 1818 -1899 (C. Graeger, 1851)

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)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1968)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1969)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1977)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1980)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1983)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1985)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1986)

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

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1998)

The Phytologist: a botanical journal - Irvine, Alexander, 1793 -1873 (William Pamplin, 1862)

Phytoplankton of the inland lakes of Wisconsin ... - Smith, Gilbert Morgan, 1885 -1959 (Pub. by the State, 1920)

Phytoplankton productivity in Lake Wabamun, Alberta and the effect of thermal effluent - Noton, L. R. (1974)

Plankton assemblages of the Gambia River, West Africa, 1983-1984 - University of Michigan. Great Lakes; Marine Waters Center. (Great Lakes and Marine Waters Center, University of Michigan, 1985)

Planktonkunde - Steuer, Adolf, 1871 - (B.G. Teubner, 1910)

Plant sociology; the study of plant communities - Braun-Blanquet, J. (Josias), 1884 -1980 (McGraw-Hill book company, inc, 1932)

Plantae preissianae sive enumeratio plantarum quas in australasia occidentali et meridionali-occidentali annis 1838-1841 collegit Ludovicus Preiss - Lehmann, Johann Georg Christian, 1792 -1860 (Sumptibus Meissneri, 1846)

Plantas Romaniae hucusque cognitas - Kanitz, Ágost, 1843 -1896 (Apud E. Demjén, 1879)

Plantes cellulaires - Montagne, Jean François Camille, 1784 -1866 (Gide, 1845)

Plants of Rhode Island : being an enumeration of plants growing without cultivation in the State of Rhode Island - Bennett, James Lawrence, 1832 -1904 (Providence Press, 1888)

Ponds and ditches - Cooke, M. C. (Mordecai Cubitt), 1825 -1914 (Society for Promoting Christian Knowledge, 1880)

A popular history of British sea-weeds, comprising their structure, fructification, specific characters, arrangement, and general distribution, with notices of some of the fresh-water Algae - Landsborough, D. (David), 1779 -1854 (Reeve and Benham, 1851)

A popular history of British sea-weeds ... with notices of some of the fresh-water Algae - Landsborough, D. (David), 1779 -1854 (Reeve, Benham and Reeve, 1849)

A popular history of British seaweeds : comprising their structure, fructification, specific characters, arrangement, and general distribution, with notices of some of the fresh-water algae - Landsborough, D. (David), 1779 -1854 (L. Reeve, 1857)

Popular Science Review (1865)

Popular Science Review (1867)

Popular Science Review (1874)

Postelsia : the year book of the Minnesota Seaside Station - Minnesota Seaside Station. (Pioneer Press, 1901)

A preliminary biological survey of waters in the Birch Mountains, Alberta - Alberta. Fish; Wildlife Division. (Fish & Wildlife Division, Dept. of Lands and Forests, 1968)

A preliminary catalogue of the flora of New Jersey - Britton, Nathaniel Lord, 1859 -1934 (Office of the Survey, 1881)

... A preliminary catalogue of the flora of New Jersey - Britton, Nathaniel Lord, 1859 -1934 (Office of the survey, 1881)

A preliminary check list of the cryptogams and phanerogams in the vicinity of Saint Louis, Missouri - Engelmann Botanical Club. Check List Committee. (The Club, 1911)

A preliminary report of the algae of the fresh waters of Connecticut - Webster, Lucia Washburn Hazen (Printed for the State Geological and Natural History Survey, 1908)

Principles of soil microbiology - Waksman, Selman A. (Selman Abraham), 1888 -1973 (Williams & Wilkins, 1927)

Prirodoslovna istraživanja - Jugoslavenska akademija znanosti i umjetnosti. (1913)

Prirodoslovna istraživanja - Jugoslavenska akademija znanosti i umjetnosti. (1916)

The problem of Krakatao as seen by a botanist - Backer, C. A. (Cornelis Andries), 1874 -1963 (The author, 1900)

Proceedings and transactions of the Liverpool Biological Society - Liverpool Biological Society. (The Society, 1890)

Proceedings and transactions of the Liverpool Biological Society - Liverpool Biological Society. (The Society, 1893)

Proceedings and transactions of the Liverpool Biological Society - Liverpool Biological Society. (The Society, 1915)

Proceedings and transactions of the Natural History Society of Glasgow - Natural History Society of Glasgow. (The Society, 1889)

Proceedings and transactions of the Royal Society of Canada. Délibérations et mémoires de la Société royale du Canada - Royal Society of Canada. (Société royale du Canada, 1888)

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 Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1841)

Proceedings of the American Academy of Arts and Sciences - American Academy of Arts; Sciences. (Metcalf and Co, 1874)

Proceedings of the American Academy of Arts and Sciences - American Academy of Arts; Sciences. (Metcalf and Co, 1917)

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

Proceedings of the Asiatic Society of Bengal - Asiatic Society of Bengal ([The Society], 1870)

Proceedings of the Bath Natural History and Antiquarian Field Club - Bath Natural History; Antiquarian Field Club. (1886)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1908)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1954)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1989)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1994)

Proceedings of the Bournemouth Natural Science Society - Bournemouth Natural Science Society (1946)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1904)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1939)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1930)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1933)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1937)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1936)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1960)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1962)

Proceedings of the Canadian Institute - Glenny, George, 1793 -1874 (Canadian Institute, 1887)

Proceedings of the Canadian Institute - Glenny, George, 1793 -1874 (Canadian Institute, 1890)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1981)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1982)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1993)

Proceedings of the Indiana Academy of Science - Indiana Academy of Science. ([s.n.], 1913)

Proceedings of the Indiana Academy of Science - Indiana Academy of Science. ([s.n.], 1911)

Proceedings of the Indiana Academy of Science - Indiana Academy of Science. ([s.n.], 1916)