The plants of Southern New Jersey with especial reference to the flora of the pine barrens and the geographic distribution of the species - Stone, Witmer. 1866 -1939 (1911)

Plants of the Bermudas : or Somer's Islands - Reade, Oswald A. (Printed at the "Royal Gazette" Office, 1885)

The plants of the eastern coast of Lake Huron and their distribution through the northern and western portions of British North America - Macoun, John, 1831 -1920 (s.n, 1876)

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Plantsman - New Hampshire Plant Growers' Association. (1995)

A pocket botanical dictionary; comprising the names, history, and culture of all plants known in Britain; with a full explanation of technical terms - Lindley, John, 1799 -1865 (J. Andrews, 1840)

A pocket synopsis of the families of British flowering plants : (based upon the system of Engler) - Grove, W. B. (William Bywater), 1848 -1938 (University Press, 1915)

Pomona College journal of entomology - Pomona College (Claremont, Calif.). Department of Biology. (Published under the patronage of Ontario-Cucamonga Citrus Association by the Dept. of Biology of Pomona College, 1909)

A popular flora of Denver, Colorado - Eastwood, Alice, 1859 -1953 (Zoe Publishing Company, 1893)

A popular handbook of the birds of Canada and the United States - Nuttall, Thomas, 1786 -1859 (Musson Book Co, 1907)

The Portland catalogue of Maine plants - Portland Society of Natural History (Me.) (Portland society of natural history, 1892)

Practical botany, structural and systematic, the latter portion being an analytical key to the wild flowering plants, trees, shrubs, ordinary herbs, sedges and grasses of the northern and middle United States east of the Mississippi - Koehler, August (H. Holt and Company, 1876)

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A preliminary catalog of the birds of Missouri - Widmann, Otto (Academy of Science of St. Louis, 1907)

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Preliminary catalogue of Anthophyta and Pteridophyta, reported as growing spontaneously within one hundred miles of New York City - Torrey Botanical Club. (1888)

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

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

Preliminary report on availability and use of waterfowl food plants in the Illinois River Valley - Bellrose, Frank C. (Frank Chapman), 1916 -2005 (Natural History Survey, 1940)

A preliminary report on the biology of Harding County, northwestern South Dakota - Visher, Stephen Sargent, 1887 -1967 (State Publishing Co, 1914)

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