Plants from the Swauk - Sharples, Stephen Paschall, 1842 -1923 (1913)

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

The plants of Michigan; simple keys for the identification of the native seed plants of the state - Gleason, Henry A. (Henry Allan), 1882 -1975 (G. Wahr, 1918)

Plants of Monroe County, New York, and adjacent territory - Beckwith, Florence. (1896)

The plants of Prince Edward Island - Erskine, D. S. (David Sterling) (Plant Research Institute, Research Branch, Canada Dept. of Agriculture, 1960)

The plants of Prince Edward Island - Erskine, D. S. (David Sterling) (Research Branch, Agriculture Canada, 1985)

Plants of Riding Mountain National Park, Manitoba - Canadian Parks Service. (Research Branch, Agriculture Canada, 1988)

Plants of west-central Montana : identification and ecology : annotated checklist - Intermountain Research Station (Ogden, Utah) (U.S. Dept. of Agriculture, Forest Service, Intermountain Research Station, 1986)

Plants of Westford, Massachusetts : Herbarium of Emily F. Fletcher - Fletcher, Emily Frances, 1845 -1923

Plants of Yellowstone National Park - McDougall, W. B. (Walter Byron), 1883 - (U.S. Govt. Print. Off, 1936)

Der Plauische Grund bei Dresden : mit Hinsicht auf Naturgeschichte und schöne Gartenkunst - Darnstedt, Johann Adolph, 1769 -1844 (In der Frauenholzischen Kunsthandlung, 1799)

Pollen - Edgeworth, Michael Pakenham, 1812 -1881 (Hardwicke & Bogue, 1877)

Popular botany; the living plant from seed to fruit - Step, Edward, 1855 -1931 (H. Holt and company, 1913)

The Popular educator: a complete encyclopaedia of elementary, advanced and technical education (Cassell, 1888)

Popular names of flowers, fruits, &c., as used in the county of Somerset and the adjacent parts of Devon, Dorset and Wilts - Macmillan, Alexander Stuart. (Western Gazette, 1922)

The Popular science monthly - Harry Houdini Collection (Library of Congress) (Popular Science Pub. Co., etc, 1887)

Popular science news, formerly Boston journal of chemistry. A popular illustrated monthly devoted to the progress in zoology, botany, mineralogy, archaeology, hygiene, invention, with related physical sciences and general scientific information - Agassiz Association. (J.R. Nichols & co. [etc.], 1866)

Popular Science Review (1875)

Populäre Botanik oder gemeinfassliche Anleitung zum Studium der Pflanze und des Pflanzenreiches. Zugleich ein Handbuch zum Bestimmen der Pflanzen auf Excursionen - Schmidlin, Eduard, 1808? -1890 (Krais & Hoffmann, 1857)

Post-fire recovery of Wyoming big sagebrush shrub-steppe in centeral and southeast Montana - Lesica, Peter. (Montana Natural Heritage Program, 2007)

The potential and current vegetation of the Sun River Game Range - Montana. Department of Fish, Wildlife,; Parks (Montana Dept. of Fish, Wildlife and Parks, 1980)

Potter's cyclopaedia of botanical drugs and preparations - Holmes, E. M. (Edward Morell), 1843 -1930 (Potter & Clarke, 1915)

Potter's cyclopedia of botanical drugs and preparations - Wren, R. C. (Richard Cranfield), 1864 -1931 (Potter & Clarke, 1900)

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

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

Practical agriculture - James, C. C. (Charles Canniff), 1863 -1916 (D. Appleton and company, 1899)

Practical agriculture - James, C. C. (Charles Canniff), 1863 -1916 (D. Appleton, 1899)

Practical botany for beginners - Bower, F. O. (Frederick Orpen), 1855 -1948 (1894)

Practical crop protection - Alberta. Soil; Crop Management Branch. (Alberta Agriculture, Food and Rural Development, 1994)

Practical hints for the field lepidopterist. I - Tutt, James William, 1858 -1911 (E. Stock, 1908)

Practical plant biochemistry - Onslow, Muriel Wheldale 1880 -1932 (University Press, 1923)

Practical plant biochemistry - Onslow, Muriel Wheldale 1880 -1932 (University press, 1920)

Practical plant biochemistry - Onslow, Muriel Wheldale 1880 -1932 (University Press, 1920)

Practical plant physiology : an introduction to original research for students and teachers of natural science, medicine, agriculture and forestry - Detmer, W. (Wilhelm), 1850 -1930 (Swan Sonnenschein, 1898)

Practical plant physiology : an introduction to original research for students and teachers of natural science, medicine, agriculture and forestry - Detmer, W. (Wilhelm), 1850 -1930 (S. Sonnenschein, 1898)

Prairie chickens on the Sheyenne National Grasslands : September 18, 1987, Crookston, Minnesota - Rocky Mountain Forest; Range Experiment Station (Fort Collins, Colo.) (U.S. Dept. of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station, 1988)

Prairie Coulees Natural Area : management plan - Alberta. Alberta Community Development. (Alberta Sustainable Resource Development, Public Lands, 2000)

Predicting the durability of forest recreation sites in northern Utah : preliminary results - Intermountain Forest; Range Experiment Station (Ogden, Utah) (U.S. Dept. of Agriculture, Forest Service, Intermountain Forest & Range Experiment Station, 1970)

A preliminary catalogue of the flora of Vancouver and Queen Charlotte Islands - British Columbia Provincial Museum. (Printed by W. H. Cullin, 1921)

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)

Preliminary classification of native wheat grass (Agropyron spp.) community types in Alberta - Alberta. Alberta Environment. (Geowest Environmental Consultants Ltd, 2001)

A preliminary classification of plant communities in the central Parkland natural sub-region of Alberta - Alberta. Alberta Sustainable Resource Development. (Geowest Environmental Consultants Ltd, 2002)

A preliminary classification of the plant communities of northeastern Montana - Montana Natural Heritage Program. (Montana Natural Heritage Program, 1991)

A preliminary classification of the Rocky Mountain shrubland communities of Alberta - Alberta. Alberta Environment. (Alberta Environment, 2000)

Preliminary inventory of Canadian weeds - Crompton, Clifford W. (Agriculture Canada, Research Branch, 1988)

A preliminary list of Maine fungi - Ricker, Percy Leroy, 1878 -1973 (1902)

Preliminary list of plants growing without cultivation in the vicinity of Manchester, New Hampshire - Batchelder, Frederick William. (Manchester institute of arts and sciences, 1909)

A preliminary list of the parasitic fungi of Idaho - United States. Division of Mycology; Disease Survey. (Division of Mycology and Disease Survey, Bureau of Plant Industry, United States Department of Agriculture, 1936)

A preliminary list of the plants of New Brunswick - Fowler, James, 1829 -1923 (Ellis, Robertson & Co, 1885)

A preliminary list of the vascular flora of Allegheny County, Pennsylvania - Shafer, John Adolph, 1863 -1918 (Carnegie Institute Museum?, 1901)

A preliminary list of the vascular plants of the Lackawanna and Wyoming valleys - Dudley, William Russel, 1849 -1911 (The Republican Press, 1887)

Prescribed fire and cattle grazing influences on the vegetation and elk use of a rough fescue community - Jourdonnais, Craig S. (1985)

Preservation of natural features and scenic views in New York City - Clarke & Rapuano. (The Department, 1974)

Price list of agricultural seeds, and treatise on permanent pasture grasses and the adulteration of their seeds - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (James Hunter, 1910)

Price list of chemical and bacteriological apparatus, chemicals and reagents manufactured and sold by Baird [and] Tatlock (London) Ltd - Baird; Tatlock, Ltd., London, (Baird [and] Tatlock, 1914)

The primeval forest types of southwestern New York - Gordon, Robert B. (Robert Benson), 1901 -1981 (University of the State of New York, 1940)

The principal species of wood: their characteristic properties - Snow, Charles H. (Charles Henry), 1863 - (J. Wiley & Sons; [etc., etc.], 1908)

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

The principles of vegetable-gardening - Bailey, L. H. (Liberty Hyde), 1858 -1954 (The Macmillan company, 1921)

The principles of vegetable-gardening - Bailey, L. H. (Liberty Hyde), 1858 -1954 (The Macmillan company; [etc., etc.], 1901)

The principles of vegetable-gardening - Bailey, L. H. (Liberty Hyde), 1858 -1954 (The Macmillan Company, 1912)

Proceedings - Nova Scotian Institute of Science. (1866)

Proceedings - Dorset Natural History; Archaeological Society.

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

Proceedings - University of Illinois at Urbana-Champaign. College of Agricultural, Consumer; Environmental Sciences. (University of Illinois at Urbana-Champaign, College of Agricultural, Consumer and Environmental Sciences, University of Illinois Extension, 2002)

Proceedings and transactions of the British Entomological and Natural History Society - British Entomological; Natural History Society. (British Entomological and Natural History Society, 1974)

Proceedings and transactions of the British Entomological and Natural History Society - British Entomological; Natural History Society. (British Entomological and Natural History Society, 1976)

Proceedings and transactions of the British Entomological and Natural History Society - British Entomological; Natural History Society. (British Entomological and Natural History Society, 1980)