Ornithological biography, or an account of the habits of the birds of the United States of America ; accompanied by descriptions of the objects represented in the work entitled The Birds of America, and interspersed with delineations of American scenery and manners - Audubon, John James, 1785 -1851 (Adam Black, 1835)

The ornithology of Illinois - Ridgway, Robert, 1850 -1929 (H.W. Rokker, printer, 1889)

O.S.U. naturalist - Ohio State University. Biological Club. (Biological Club of Ohio State University, 1902)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1887)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1897)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1909)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1908)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1918)

Ouachita National Forest, Arkansas-Oklahoma - United States. Forest Service. Southern Region. (U.S. Govt. Print. Off, 1937)

Our native trees and how to identify them : a popular study of their habits and their peculiarities - Keeler, Harriet L. (Harriet Louise), 1846 -1921 (C. Scribner's Sons, 1900)

Our native trees and how to identify them; a popular study of their habits and their peculiarities - Keeler, Harriet L. (Harriet Louise), 1846 -1921 (C. Scribner's Sons, 1912)

Our native trees and how to identify them; a popular study of their habits and their peculiarities - Keeler, Harriet L. (Harriet Louise), 1846 -1921 (C. Scribner's Sons, 1910)

Our native trees and how to identify them; a popular study of their habits and their peculiarities - Keeler, Harriet L. (Harriet Louise), 1846 -1921 (C. Scribner's Sons, 1913)

Our native trees and how to identify them; a popular study of their habits and their peculiarities - Keeler, Harriet L. (Harriet Louise), 1846 -1921 (C. Scribner's Sons, 1917)

Our native trees and how to identify them a popular study of their habits and their peculiarities - Keeler, Harriet L. (Harriet Louise), 1846 -1921 (McClelland, Goodchild & Stewart, 1900)

Our native trees and how to identify them; a popular study of their habits and their peculiarities - Keeler, Harriet L. (Harriet Louise), 1846 -1921 (Scribner, 1902)

Our trees. A popular account of the trees in the streets and gardens of Salem, and of the native trees of Essex County, Massachusetts, with the location of trees, and historical and botanical notes - Robinson, John, 1846 -1925 (Printed by N. A. Horton and Son, 1891)

Our trees, how to know them : photographs form nature by Arthur I. Emerson, with a guide to their recognition at any season of the year and notes on their characteristics, distribution, and culture, by Clarence M. Weed - Weed, Clarence Moores, 1864 -1947 (J.B. Lippincott Company, 1918)

Our trees, how to know them; photographs from nature - Weed, Clarence Moores, 1864 -1947 (Lippincott, 1936)

Our trees, how to know them: photographs from nature by Arthur I. Emerson, with a guide to their recognition at any season of the year and notes on their characteristics, distribution, and culture - Weed, Clarence Moores, 1864 -1947 (J.B. Lippincott, 1918)

An outline of plant geography (The Macmillan company, 1926)

Outlines of botany for the high school laboratory and classroom (based on Gray's Lessons in botany) - Leavitt, Robert Greenleaf, 1865 - (American Book Co, 1901)

Outlines of creation - Noyce, Elisha. (Ward & Lock, 1858)

Outlines of medical botany :comprising vegetable anatomy and physiology...and a glossary of terms - Reid, Hugo. (Maclachlan, Stewart & Co, 1896)

Oxford gardens, based upon Daubeny's Popular guide to the physick garden of Oxford: with notes on the gardens of the colleges and on the University park - Gunther, R. T. (Robert Theodore), 1869 -1940 (Parker & son; [etc., etc.], 1912)

Oxford gardens. Based upon Daubeny's Popular guide to the physick garden of Oxford : with notes on the gardens of the colleges and on the University Park - Gunther, R. T. (Robert Theodore), 1869 -1940 (Parker, 1912)

Die palaeobotanische Literatur : bibliographische Übersicht über die Arbeiten aus dem Gebiete der Palaeobotanik - Jongmans, W. (Willem), 1878 -1957 (Fischer, 1913)

Palaeontology - Palaeontological Association (Palaeontological Association, 1997)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1897)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1896)

Pamphlets on forest protection (1900)

Pamphlets on forest utilization (1900)

Pamphlets on forestry (1900)

Pamphlets on forestry in California (1900)

Pamphlets on forestry in Kansas (1900)

Pamphlets on forestry in Maryland (1900)

Pamphlets on forestry in Massachusetts (1900)

Pamphlets on forestry in Michigan (1900)

Pamphlets on forestry in Montana (1900)

Pamphlets on forestry in Nebraska (1900)

Pamphlets on forestry in North Carolina (1900)

Pamphlets on forestry in North Dakota and South Dakota (1900)

Pamphlets on forestry in Ohio (1900)

Pamphlets on forestry in Pennsylvania (1900)

Pamphlets on forestry in Tennessee (1900)

Pamphlets on forestry in Texas (1900)

Pamphlets on silviculture (1899)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1963)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1990)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 2000)

Papers from the Department of forest entomology - Osborn, Herbert 1856 -1954 (1922)

Papers from the Department of Forest Entomology - New York. College of Forestry, Syracuse. Dept. of Forest Entomology. (The University, 1922)

Papers on botany - Stout, A.B. (Arlow Burdette ) 1876 -1957 (1921)

Parasitic fungi of Illinois. Part II, Erysipheae, Lév - Earle, F. S. (Franklin Sumner), 1856 -1929 (J.W. Franks & Sons, 1887)

Parasitic fungi of Illinois / by T.J. Burrill - Earle, F. S. (Franklin Sumner), 1856 -1929 (J. W. Franks, 1887)

Paris International Exhibition, 1900 - Macoun, James Melville, 1862 -1920 (s.n.], 1900)

Park and cemetery - Haight, R. J. (Rufus J.) (R.J. Haight, 1898)

Park and cemetery - Haight, R. J. (Rufus J.) (R.J. Haight, 1899)

Park and cemetery and landscape gardening - Haight, R. J. (Rufus J.) (R.J. Haight, 1904)

Park and cemetery and landscape gardening - Haight, R. J. (Rufus J.) (R.J. Haight, 1903)

Park and cemetery and landscape gardening - Haight, R. J. (Rufus J.) (R.J. Haight, 1908)

Part I. The living flora of West Virginia - Millspaugh, Charles Frederick, 1854 -1923 (Wheeling news litho. co, 1913)

Partial stock list of everything pertaining to horticulture for 1905 now in stock at the Universal Horticultural Establishment - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (W.A. Manda, 1905)

Partial stock list of everything pertaining to horticulture for 1907 : now in stock at the Universal Horticultural Establishment - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (W.A. Manda, 1907)

Pehr Kalms Resa till Norra Amerika - Kalm, Pehr, 1716 -1779 (Tidnings & tryckeri-aktiebolagets tryckeri, 1904)

Pennsylvania trees - Illick, Joseph S. (Joseph Simon), 1884 -1967 (W.S. Ray, State Printer, 1914)

Pennsylvania trees - Illick, Joseph S. (Joseph Simon), 1884 -1967 (W. S. Ray, State Printer, 1915)

Pepacton - Burroughs, John, 1837 -1921 (Houghton, Mifflin, 1901)

Pepacton - Burroughs, John, 1837 -1921 (Houghton Mifflin company, 1909)

Pepacton - Burroughs, John, 1837 -1921 (Houghton Mifflin, 1895)

Pepacton - Burroughs, John, 1837 -1921 (Houghton, Mifflin, 1902)

Pepacton - Burroughs, John, 1837 -1921 (Houghton, Mifflin, 1895)