Plankton diatom assemblages in Lake Michigan - Stoermer, Eugene F., 1934 - (1969)

The plankton of Lake Winnebago and Green Lake - Marsh, C. Dwight (Charles Dwight), 1855 -1932 (Published by the State, 1903)

The plankton of the Illinois river, 1894-1899, with introductory notes upon the hydrography of the Illinois river and its basin - Kofoid, Charles A. (Charles Atwood), 1865 -1947 (1903)

The plankton of the Illinois river, 1894-1899, with introductory notes upon the hydrography of the Illinois river and its basin - Kofoid, Charles A. (Charles Atwood), 1865 -1947 (1908)

Plankton of the offshore waters of the Gulf of Maine - Bigelow, Henry B. (Henry Bryant), 1879 -1967 (Govt. Print. Off, 1926)

Das Plankton unserer Seen - Amman, Hans. (Hartleben, 1900)

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

The plant cell : its modifications and vital processes, a manual for students - Royal College of Physicians of Edinburgh. (Charles Griffin, 1910)

The plant cell : its modifications and vital processes, a manual for students - Haig, Harold Axel. (Charles Griffin, 1910)

The plant cell, its modifications and vital processes; a manual for students - Haig, Harold Axel. (C. Griffin and Company, Ltd, 1910)

Plant morphology - Haupt, Arthur W. (Arthur Wing), 1894 - (McGraw-Hill, 1953)

The Plant world - Plant World Association. (Plant World Association [etc.], 1909)

The Plant world - Plant World Association. (Plant World Association [etc.], 1913)

The Plant world - Plant World Association. (Plant World Association [etc.], 1918)

Planterester i Norske torvmyrer : et bidrag til den norske vegetations historie efter den sidste istid - Holmboe, Jens 1880 -1943 (J. Dybwad, A.W. Brøggers boktr, 1903)

The planton of Lake Winnebago and Green Lake - Marsh, C. Dwight (Charles Dwight), 1855 -1932 (Published by the State, 1903)

Plants of Iowa; a preliminary list of the native and introduced plants of the state, not under cultivation - Greene, Wesley. (Bishard brothers, printers, 1907)

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)

A popular handbook to the microscope - Wright, Lewis, 1838 -1905 (Religious Tract Society, 1895)

A popular handbook to the microscope - Wright, Lewis, 1838 -1905 (Religious Tract Society, 1910)

Popular Science Review (1872)

Popular Science Review (1877)

Pozsonyi Orvos-Termeszettudomanyi Egyesulet Kozlemenyei - Verein für natur- und heilkunde, Pressburg (1894)

Pozsonyi Orvos-Termeszettudomanyi Egyesulet Kozlemenyei - Verein für natur- und heilkunde, Pressburg (1901)

Pozsonyi Orvos-Termeszettudomanyi Egyesulet Kozlemenyei - Verein für natur- und heilkunde, Pressburg (1905)

A practical treatise on the use of the microscope, including the different methods of preparing and examining animal, vegetable, and mineral structures - Quekett, John, 1815 -1861 (H. Bailliere; [etc., etc.], 1852)

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 biological survey of waters in the Maybelle River, Keane Creek, Crown Creek, Old Fort River and Richardson River drainages - Alberta. Fish; Wildlife Division. (Fish and Wildlife Division, Dept. of Lands and Forests, 1968)

Preussische Diatomeen - Schumann, Julius, 1810 -1868 (1862)

Principles of animal ecology - Allee, W. C. (Warder Clyde), 1885 -1955 (Saunders Co, 1949)

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

Das Problem des Lebens; biologische Studien - Hartmann, Eduard von, 1842 -1906 (H. Haacke, 1906)

Proceedings and transactions of the Liverpool Biological Society - Liverpool Biological Society. (The Society, 1900)

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

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, 1913)

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, 1915)

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, 1916)

Proceedings and transactions of the Texas Academy of Science - Texas Academy of Science. (The Academy, 1941)

Proceedings - Cambridge Philosophical Society. Mathematical and physical sciences - Cambridge Philosophical Society. (Cambridge Philosophical Society [etc.], 1910)

Proceedings of the 6th International Conference on Coelenterate Biology : the Leeuwenhorst, Noordwijkerhout, the Netherlands, 16-21 July 1995 - Ofwegen, L. P. van (Leendert P.), 1953 - (Nationaal Natuurhistorisch Museum, 1997)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1890)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1898)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1900)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1910)

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, 1902)

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, 1989)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1859)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1866)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1871)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1875)

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, 1917)

Proceedings of the California Academy of Sciences. 3d ser, Geology - California Academy of Sciences (The Academy, 1897)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1926)