Phegea - Vlaamse Vereniging voor Entomologie. (Vlaamse Vereniging voor Entomologie, 2003)

Philadelphia flower & garden show - Pennsylvania Horticultural Society. (The Society, 1977)

Philadelphia flower & garden show - Pennsylvania Horticultural Society. (The Society, 1976)

Philadelphia flower show - Pennsylvania Horticultural Society. (The Society, 1986)

Philadelphia flower show - Pennsylvania Horticultural Society. (The Society, 1994)

Philosophia botanica - Linné, Carl von, 1707 -1778 (P. Marin, 1792)

The Philosophical transactions of the Royal society of London, from their commencement in 1665, in the year 1800 - Royal Society (Great Britain) (Printed by and for C. and R. Baldwin, 1809)

PHS news - Pennsylvania Horticultural Society. (The Society, 1965)

PHS news - Pennsylvania Horticultural Society. (The Society, 1984)

PHS news - Pennsylvania Horticultural Society. (The Society, 1986)

The physiology of plants; a treatise upon the metabolism and sources of energy in plants - Pfeffer, W. (Wilhelm), 1845 -1920 (Clarendon press, 1900)

Physiotypia plantarum Austriacarum : die Gefässpflanzen Österrichs in Naturselbstdruck mit besonderer Berücksichtigung der Nervation in den Flächenorganen der Pflanzen - Ettingshausen, Constantin, Freiherr von, 1826 -1897 (F. Tempsky in Prag, 1873)

La phytographie; ou, L'art de décrire les végétaux considérés sous différents points de vue - Candolle, Alphonse de, 1806 -1893 (G. Masson, 1880)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1974)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1989)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1997)

The Phytologist: a botanical journal - Irvine, Alexander, 1793 -1873 (William Pamplin, 1857)

The Phytologist: a botanical journal - Irvine, Alexander, 1793 -1873 (William Pamplin, 1858)

The Phytologist: a popular botanical miscellany - Newman, Edward, 1801 -1876 (John van Voorst, 1841)

The Phytologist: a popular botanical miscellany - Newman, Edward, 1801 -1876 (John van Voorst, 1847)

Phytoneuron (Guy L. Nesom, 2010)

Phytoneuron (Guy L. Nesom, 2011)

Phytoneuron (Guy L. Nesom, 2015)

Phytoneuron (Guy L. Nesom, 2019)

Phytoneuron (Guy L. Nesom, 2020)

Le piante fanerogame della Svissera insubrica : enumerate seconde il metodo decandolliano - Favrat, Louis, 1827 -1893 (H. Georg, 1890)

Le piante fanerogame della Svizzera insubrica : enumerate secondo il methodo decandolliano - Favrat, Louis, 1827 -1893 (H. Georg, 1890)

Pierre Pena et Mathias de Lobel - Legré, Ludovic, 1838 -1904 (H. Aubertin & G. Rolle, 1899)

Pitzonka's Pansy Farm, "The home of the pansy" : perennials, bulbs, rock plants - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Pitzonka's Pansy Farm, 1934)

Pitzonka's Pansy Farm, "The home of the pansy" : rock plants, bulbs, perennials - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Pitzonka's Pansy Farm, 1933)

Plan and plant now for a beautiful spring - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Harold Lyke, 1950)

Plant Barr's bulbs and plants now : save in costs-gain in results - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (B.F. Barr & Co, 1938)

Plant bulbs! - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Gardenville Bulb Growers, 1938)

Plant bulbs - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Gardenville Bulb Growers, 1939)

Plant bulbs now! - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Gardenville Bulb Growers, 1937)

Plant bulbs now for a delightful spring garden - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Malmo Nurseries and Seed Stores, 1944)

Plant bulbs now for spring flowers - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Beckert Seed & Bulb Co, 1932)

Plant bulbs now for spring flowers - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Gardenville Bulb Growers, 1936)

Plant . . bulbs this fall and have beautiful blooms next spring - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (David J. Scott Company, 1952)

Plant bulbs this fall for flowers next spring : low prices (see inside) - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alexander Forbes & Co, 1939)

Plant Bunton's imported Holland bulbs this fall for a more beautiful garden - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Bunton Seed Company, Incorporated, 1953)

Plant culture; a working handbook of every day practice for all who grow flowering and ornamental plants in the garden and greenhouse - Hottes, Alfred Carl, 1891 -1955 (A. T. De La Mare Co., Inc, 1921)

Plant culture; a working handbook of every day practice for all who grow flowering and ornamental plants in the garden and greenhouse - Hottes, Alfred Carl, 1891 -1955 (A. T. De La Mare co., inc, 1921)

Plant explorations : ornamentals in Italy, southern France, Spain, Portugal, England, and Scotland - Meyer, Frederick G. 1917 -2006 (U. S. Dept. of Agriculture in cooperation with Longwood Gardens of the Longwood Founcation, 1959)

The plant explorer's notebook - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (The Barnes Importers, 1951)

Plant-geography upon a physiological basis - Balfour, Isaac Bayley, 1853 -1922 (Clarendon Press, 1903)

Plant Holland bulbs this fall for flowers next spring - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Howard-Hickory Nurseries, 1948)

Plant Holland bulbs this fall for flowers next spring - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Baldwin Garden Specialties, Inc, 1948)

Plant Holland bulbs this fall for flowers next spring - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (B. F. Barr & Son Nurseries, 1948)

Plant Holland bulbs this fall for flowers next spring - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (B.F. Barr & Son Nurseries, 1950)

Plant Holland bulbs this fall : for flowers next spring!, 1948 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Jardin des Iris, 1948)

Plant Holland bulbs this fall–for flowers next spring : 1948 [price list] - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Roy V. Ashley, 1948)

Plant Holland bulbs this fall : for flowers next spring, 1948 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Richards' Plants for Home and Garden, 1948)

Plant Holland bulbs this fall for flowers next spring : 1948 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Wassenberg, 1948)

Plant Holland bulbs this fall for flowers next spring : fall 1950 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Paul's Flowers, 1950)

Plant Holland bulbs this fall for flowers next spring : fall 1950 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Brentwood Berry Gardens, 1950)

Plant importation rule 1925-1926 - Japan. Nōrinshō. (1925)

Plant inventory - United States. Agricultural Research Service. (Northeastern Region, Agricultural Research Center-West, 1923)

Plant inventory - United States. Agricultural Research Service. (Northeastern Region, Agricultural Research Center-West, 1929)

Plant inventory - United States. Agricultural Research Service. (Northeastern Region, Agricultural Research Center-West, 1934)

Plant inventory - United States. Agricultural Research Service. (Northeastern Region, Agricultural Research Center-West, 1942)

Plant inventory - United States. Agricultural Research Service. (Northeastern Region, Agricultural Research Center-West, 1958)

Plant inventory - United States. Agricultural Research Service. (Northeastern Region, Agricultural Research Center-West, 1966)

Plant inventory - United States. Agricultural Research Service. (Northeastern Region, Agricultural Research Center-West, 1968)

Plant inventory - United States. Agricultural Research Service. (Northeastern Region, Agricultural Research Center-West, 1969)

Plant life through the ages : a geological and botanical retrospect - Seward, A. C. (Albert Charles), 1863 -1941 (Hafner, 1933)

Plant list - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (L.N. Roberson Co, 1952)

Plant list, 1946 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (L.N. Roberson Co, 1946)

Plant list, 1948-49 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (L.N. Roberson Co, 1948)

Plant names - Lindsay, Thomas Somerville Reeves, 1854 - (Sheldon, 1923)

Plant names, scientific and popular, including in the case of each plant the correct botanical name in accordance with the reformed nomenclature, together with botanical and popular synonyms ... - Lyons, A. B. (Albert Brown), 1841 -1926 (Nelson, Baker & Co, 1900)

The Plant of the Month Club December offerings - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (All America Garden Club, 1946)

Plant propagation; greenhouse and nursery practice - Kains, M. G. (Maurice Grenville), 1868 -1946 (Orange Judd company, 1916)

Plant spring flowering bulbs now - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (J. Manns & Co, 1950)

Plant spring-flowering bulbs this fall - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Carroll Gardens, 1942)

Plant this fall - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Hillenmeyer Nurseries, 1936)

Plant this fall for beauty next spring : fall 1947 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Inter-State Nurseries, 1947)

Plant this fall for beauty next spring : fall 1948 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Inter-State Nurseries, Inc, 1948)

Plant this fall for beauty next spring : fall 1949 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Inter-State Nurseries, 1949)

Plant this fall for beauty next spring : fall 1950 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Inter-State Nurseries, Inc, 1950)

Plant this fall for beauty next spring : fall 1951 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Inter-State Nurseries, 1951)

Plant this fall for beauty next spring : fall 1952 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Inter-State Nurseries, 1952)

Plant this fall for beauty next spring : fall 1953 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Inter-State Nurseries, 1953)

Plant this fall for beauty next spring : fall 1954 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Bobbink & Atkins, 1954)

Plant this fall for beauty next spring : fall 1954 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Inter-State Nurseries, 1954)

Plant this fall for early spring flowers : shrubs, trees, vines, iris, perennials, tulips, crocuses, peonies, hyacinths, narcissi [catalog] - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (L.C. Casler, 1930)

Plant this fall for early spring flowers : tulips, crocuses, peonies, hyacinths, shrubs, trees, iris, vines perennials [catalog] - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (L.C. Casler, 1931)

To plant this fall for springtime bloom - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Hovey & Co, 1934)

Plant this fall sale : eat luscious red raspberries next spring - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Benton County Nursery Co, 1954)

Plant tulips this fall for blooms next spring ... - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (J. Chas. McCullough Seed Co, 1948)

Plantae Europeae.Enumeratio systematica et synonymica plantarum phaenerogamicarum in Europa sponte crescentium vel mere inquilinarum - Richter, Karl, 1855 -1891 (W. Engelmann, 1890)

Plantae Postianae - Autran, Eugène, 1855 -1912 (G. Bridel, 1892)

Plantae rariores quas in itinere per oras Jonii ac Adriatici Maris et per regiones Samnii ac Aprutii - Gussone, Giovanni, 1787 -1866 (Ex Regia Typographia, 1826)

Plantae vasculares seu cotyledoneae Scandanaviae, nempe Sveciae et Norvegiae : juxta regni vegetabilis systema naturale digestae - Beurling, Pehr Johan, 1800 -1866 (P. A. Norstedt, 1859)

Plantarum vascularium genera :secundum ordines naturales digesta eorumque differentiae et affinitates tabulis diagnostacis expositae - Weidmann. (Libraria Weidmannia, 1836)

As plantas ornamentaes da flora brasilica: e o seu papel como factores da salubridade publica, da esthetica urbana e artes decorativas nacionaes - Hoehne, F. C. (Frederico Carlos), 1882 -1959 (Secretaria da Agricultura, Insdustria e Commercio do Estado de Sao Paulo, 1936)

Plantas Romaniae hucusque cognitas - Kanitz, Ágost, 1843 -1896 (Apud E. Demjén, 1879)