Principles of botany - Bergen, Joseph Y. (Joseph Young), 1851 -1917 (Ginn & Company, 1906)

Principles of comparative physiology - Carpenter, William Benjamin, 1813 -1885 (John Churchill, 1854)

The principles of mushroom growing and mushroom spawn making - Duggar, Benjamin M. (Benjamin Minge), 1872 -1956 (Gov't print. off, 1905)

Principles of physiology, general and comparative - Carpenter, William Benjamin, 1813 -1885 (John Churchill, 1851)

The principles of plant-teratology - Worsdell, Wilson Crosfield (The Ray Society, 1915)

Proceedings - Dorset Natural History; Archaeological Society.

Proceedings - Entomological Society of Canada (1863-1871) (Entomological Society of Ontario, 1900)

Proceedings and Transactions of the Croydon Microscopical & Natural History Club - Croydon Microscopical; Natural History Club. (1889)

Proceedings and transactions of the Natural History Society of Glasgow - Natural History Society of Glasgow. (The Society, 1883)

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

Proceedings and transactions of the Natural History Society of Glasgow - Natural History Society of Glasgow. (The Society, 1892)

Proceedings and transactions of the Nova Scotian Institute of Natural Science - Nova Scotian Institute of Natural Science. (Nova Scotian Institute of Natural Science, 1863)

Proceedings and transactions of the Nova Scotian Institute of Natural Science - Nova Scotian Institute of Natural Science. (Nova Scotian Institute of Natural Science, 1879)

Proceedings and transactions of the Nova Scotian Institute of Natural Science - Nova Scotian Institute of Natural Science. (Nova Scotian Institute of Natural Science, 1886)

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, 1904)

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, 1883)

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 South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1943)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1947)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1953)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1956)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1959)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1962)

Proceedings - Cambridge Philosophical Society. Mathematical and physical sciences - Cambridge Philosophical Society. (Cambridge Philosophical Society [etc.], 1900)

Proceedings - Dorset Natural History and Archaeological Society - Dorset Natural History; Archaeological Society. (1877)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1876)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1893)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1894)

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, 1857)

Proceedings of the ... annual meeting of the Florida State Horticultural Society - Florida State Horticultural Society. Meeting. (The Society, 1909)

Proceedings of the Bath Natural History and Antiquarian Field Club - Bath Natural History; Antiquarian Field Club. (1870)

Proceedings of the Bath Natural History and Antiquarian Field Club - Bath Natural History; Antiquarian Field Club. (1898)

Proceedings of the Biological Society of Washington - Smithsonian Institution (Biological Society of Washington, 1921)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1856)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1907)

Proceedings of the Bournemouth Natural Science Society - Bournemouth Natural Science Society (1910)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1885)

Proceedings of the Elliott Society of Science & Art of Charleston, South Carolina - Elliott Society of Science & Art. (s.n, 1859)

Proceedings of the Indiana Academy of Science - Indiana Academy of Science. ([s.n.], 1893)

Proceedings of the Indiana Academy of Science - Indiana Academy of Science. ([s.n.], 1900)

The Proceedings of the Iowa Academy of Science - Iowa Academy of Science (The Academy, 1909)

The Proceedings of the Iowa Academy of Science - Iowa Academy of Science (The Academy, 1916)

Proceedings of the Linnean Society of London - Linnean Society of London. (Published for the Linnean Society of London by Academic Press [etc.], 1906)

Proceedings of the Linnean Society of New South Wales - Linnean Society of New South Wales. (Linnean Society of New South Wales, 1880)

Proceedings of the Linnean Society of New South Wales - Linnean Society of New South Wales. (Linnean Society of New South Wales, 1888)

Proceedings of the Linnean Society of New South Wales - Linnean Society of New South Wales. (Linnean Society of New South Wales, 1906)

Proceedings of the Linnean Society of New South Wales - Linnean Society of New South Wales. (Linnean Society of New South Wales, 1953)

Proceedings of the Literary and Philosophical Society of Liverpool - Literary; Philosophical Society of Liverpool. (1856)

Proceedings of the Natural history society of Dublin for the session ... - Natural History Society of Dublin. (Printed for the Society, 1878)

Proceedings of the Natural History Society of Glasgow - Natural History Society of Glasgow. (Natural History Society of Glasgow, 1880)

Proceedings of the Nova Scotian Institute of Science - Nova Scotian Institute of Science. (Nova Scotian Institute of Science, 1993)

Proceedings of the Onondaga Academy of Science - Onondaga Academy of Science. (Published by the Academy, 1903)

Proceedings of the Perthshire Society of Natural Science - Perthshire Society of Natural Science. (1880)

Proceedings of the Rochester Academy of Science - Rochester Academy of Science. (The Academy, 1889)

Proceedings of the Rochester Academy of Science - Rochester Academy of Science. (The Academy, 1891)

Proceedings of the Rochester Academy of Science - Rochester Academy of Science. (The Academy, 1910)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1884)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1909)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1911)

Proceedings of the Royal Society of Edinburgh - Royal Society of Edinburgh. (Royal Society of Edinburgh, 1878)

Proceedings of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (South London Entomological and Natural history Society, 1906)

Proceedings of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (South London Entomological and Natural history Society, 1910)