Ochroma obtusa Rowlee, J. Wash. Acad. Sci. 9: 166. 1919
Columbia: Santa Marta, H.H. Smith 829, 1898-1901, ? Isotype
Ochrosia sandwicensis A. Gray, Proc. Am. Acad. 5: 333. 1861-2
Hawaiian Islands: Oahu, O. Degener et al. 20833, 2 July 1950, Topotype
Ocotea flavescens Rusby, Descriptions of Three Hundred New Species of South American Plants pp. 20-21. 1920
Columbia: Santa Marta, H.H. Smith 1762 (1898-1901), ? Isotype
Odonia viridiflora Rose, Contr. U.S. Nat. Herb. 10: 103. 1906
Mexico: Guerrero, Iguala Canyon, C.G. Pringle 10324, 8 Oct. 1906, Paratype & Topotype
Odontites catalaunica Sen., Bot. Soc. Arag. 11: 211. 1912
Spain: Catalogne, Pyrénées, Ripoll au Catllar, F. Sennen 1009, Sept. 1910, Topotype
Odontites Corsica G. Don, Gen. Syst. 4: 611. 1837
Corsica: Montagne de Cagna, J. Stefani, 4 août 1903, Topotype
Odontites powellii Maire f. rubricaulis Sauv., Publication unknown
Morocco: Moyen Atlas central, Ch. Sauvage 13914, 5 Oct. 1956, ? Type Collection Material
Odontonema bracteolatum (Jacq.) Kuntze var. parviflorum Leonard, Contr. U.S. Natl. Herb. 31: 399. 1958
Columbia: Santa Marta, H.H. Smith 1389, 1898-1901, ? Isotype
Odontosoria guatemalensis Christ, Bull. Soc. Bot. Genève, ser. 2 1: 229. 1909
Guatemala: Finca Naranjo, Chicacao, J.F. Brenckle 47-93, 14 Mar. 1947, Topotype
Oenothera boothii Dougl. ssp. inyoensis Munz, North Am. Fl. Ser. 2, Pt. 5: 153. 1965
U.S.A.: California, Inyo Co., Saline Valley, P.A. Munz 18033, 8 Apr. 1967, Topotype
Oenothera brevipes Gray ssp. arizonica Raven, Un. Calif. Pub. Bot. 34: 84. 1962
U.S.A.: Arizona, Yuma Co., 2 miles north of Yuma, P.H. Raven 14835, 14 March 1960, Paratype
Oenothera caespitosa Nutt. ssp. navajoensis Wagner, Stockhouse & Klein
U.S.A.: Utah, Carbon County, Price, Mosquin & Mulligan 5024, 10 June 1963, Paratype
Oenthera caespitosa Nutt. ssp. navajoensis Wagner, Stockhouse & Klein, Monog. Syst. Bot. Missouri Bot. Gard. 12: 66. 1985
U.S.A.: Utah, Kane Co., along the Paria 'River', 8 road miles northwest of Hwy. 89A, A. Cronquist 10202, 28 May 1965, Isotype
Oenothera chicaginensis de Vries ex Renner var. minutiflora Rostanski & Jehlik
Czechoslovakia: Trutnov, cult. horto Pruhonice, Jehlik & Rostanski, 7 Aug. 1970, Topotype
Oenothera clavaeformis Torrey & Frémont ssp. citrina Raven, U. Calif. Pub. Bot. 34: 108-109. 1962
U.S.A.: Nevada, Washoe Co., 14.3 miles east of Sparks, P.H. Raven 14273, 28 May 1959, Paratype
Oenothera clavaeformis Torrey & Frémont ssp. funerea Raven, U. Calif. Pub. Bot. 34: 106. 1962
U.S.A.: California, Inyo Co., 2.7 miles south-east of junction to Scotty's Castle, P.H. Raven 11987, 29 Mar. 1958, Paratype
Oenothera clavaeformis Torrey & Frémont ssp. integrior Raven, U. Calif. Pub. Bot. 34: 106-107. 1962
U.S.A.: Nevada, Lander Co., road to Potts, Raven & Solbrig 13533, Paratype
Oenothera clavaeformis Torrey & Frémont ssp. rubescens Raven, U. Calif. Pub. Bot. 34: 103. 1962
U.S.A.: Arizona, Maricopa Co., 4 miles east of Sentinel, P.H. Raven 14825, 13 Mar. 1960, Paratype
Oenothera claveformis Torrey & Frémont ssp. yumae Raven, U. Calif. Pub. Bot. 34: 104. 1962
U.S.A.: California, Imperial Co., 7.6 miles east of Holtville, P.H. Raven 11492, 25 Jan. 1958, Paratype
Oenothera confusa P.H. Raven
U.S.A.: California, San Bernardino County, San Bernardino Valley, north of Upland, A.J. Breitung 15060, 14 May 1953, Paratype
Oenothera deltoides Torrey & Frémont, Aliso 2: 81. 1949
U.S.A.: California, grown from seeds from sand dunes east of Antiock, Contra Costa Co., P.A. Munz 12201, Botanic Garden, P.A. Munz 14436, June 1949, Topotype
Oenothera dentata Cav. var. johnstonii Munz, Bot. Gaz. 85. 259. 1928
U.S.A.: California, Kern County, western Mojave Desert, Munz & Gregory 23313, 19 April 1958, Topotype
Oenothera kernensis Munz, Am. J. Bot. 18: 737. 1931
U.S.A.: California, Kern Co., Walker Pass, L.S. Rose 62042, 21 May 1962, Topotype
Oenothera munzii Raven, U. Calif. Pub. Bot. 34: 91. 1962
U.S.A.: California, Inyo Co., 3.2 miles south of Mesquite Spring, P.H. Raven 12001, 29 Mar. 1958, Paratype
Oenothera nissensis Rostanski, Fragm. Florist. & Geobot., Krakow 11: 508. 1965
Poland: Silesia Inferior, Nysa, K. Rostanski, 12 July 1968 (Fl. Sil. ex. 911), Topotype
Oenothera pseudochicaginensis Rostanski, Fragmen. Florist. & Geobot., Krakow 11: 504-506. 1965
Poland: Silesia Inferior, Wratislaviae, K. Rostanski, 15 July 1968, (Fl. Sil. ex. 912), Topotype
Oenothera rubicapitata R.R. Gates, Phil. Trans. Royal Soc. London, Ser. B, 226: 363. 1936
U.S.A.: North Dakota, Richland Co., Kindred, O.A. Stevens 1087, 20 Aug. 1949, Topotype
Oenothera ×slovaca Jehlik & Rostanski, Folia Geobot. Phytotax. 14(4): 413-416, 1979
Czechoslovakia: Nové Zámky, cult. horto Pruhonice, V. Jehlik, 14 Aug. 1970, Topotype
Oenothera turoviensis Rostanski, Fragm. Florist. & Geobot., Krakow 11: 514-517. 1965
Poland: Silesia Inferior, Turoszow, J. Aniol, 13 Aug. 1969 (Fl. Sil. ex. 909), Topotype
Oenothera wigginsii Klein, Aliso 5: 180. 1962
Mexico: Baja California, 5 miles N of San Quintin, J.H. Thomas 142, 23 Mar. 1949, Paratype
Olea europaea L. var. cerasiformis Webb, Publication unknown
Canary Islands: Nivaria, Los Silos, E.R. Sventenius 78, 20 Oct. 1947, ? Topotype
Olea sandwicensis A. Gray, Proc. Amer. Acad. 5: 331. 1862
Hawaiian Islands: Oahu, P. Holman, 30 Apr. 1939, Topotype
Oligosporus pycnocephalus Less., Linnaea 6: 524. 1831
U.S.A.: California, San Francisco, Golden Gate Heights, L.S. Rose 49149, 5 Aug. 1949, Topotype
Onobrychis arenaria Kitaibel in Willd., Enum. plant. h.b. Berolin. Suppl. p. 51; Seringe in DC. Prodr. 2: 345. 1825
Hungary: ad Pestinum, Borbas (Fl. Ex. Austro-Hung. 401), Topotype
Onoclea struthiopteris (L.) Hoffm. f. raymondii Boivin, Bull. Soc. Bot. France 108: 414. 1961
Sweden: Abisko Ostra, côté nord du Torneträsk, Boivin et al. 7173, 29 juillet 1950, Holotype
Ononis antiquorum L. var. transiens Rouy sous-var. albiflora Gavelle, Publication unknown
France: Laure, E. Gavelle, 12 juillet 1961, ? Type Collection Material
Ononis cephalotes Boiss. var. minutifolia Pau & F.Q., Publication unknown
Europe: Mauritania, Hauta-el Kasdir, P. Font i Quer, 9 July 1932, ? Type Collection Material
Ononis saxicola Boiss. et Reut., Pugillus Pl. Nov. Africae borealis Hispanieque australis 32. 1852
Spain: Baetica, San Cristobal, supra Grazalema, Gros, 14 June 1922, Topotype
Ononis spinosa L. ssp. leiosperma Sirj. var. genuina Sirj., Publication unknown
Iran: Kazvin, Keredj, K.H. & F. Rechinger 6719, 20 Aug. 1948, ? Type Collection Material
Ononis subspicata Lagasca, Genista y Antillideas de Espana y Portugal 73. 1872
Spain: Baetica, Arcos de la Frontera, P. Font i Quer, 19 June 1925, Topotype
Onosma euboicum Rech. f., Bot. Jahrb. 80: 378. 1961
GREECE: Ins. Euboea, Montes Kandili, K.H. Rechinger 17028, 30 May 1955, Isotype
Onosma lucanum Lacaita, Nuov. Giorn. Bot. Ital. n.s. 31: 33-34. 1924
ITALY: Lucania, Prov. di Potenza, C. Lacaita, 12 June 1924, Topotype
Onosma transrhymnense Klokov, apud Popov in Not. Syst. Herb. Inst. Bot. Acad. Sci. URSS 14: 301. 1953
U.S.S.R.: Prov. Krasnojarsk, in steppa opp. Minussinsk, N. Martjanov, June 1900, Isotype
Ophioderma falcatum Degener, Flora Hawaiiensis, 1932
Hawaiian Islands: Oahu, Degener et al. 12, 386, 30 April 1939, Topotype
Opuntia multigeniculata Clokey
U.S.A.: Nevada, Clark Co., east of Wilson's Ranch, road from Blue Diamond mine to mill, I.W. Clokey 8430, 13 July 1939, Isotype
Orchis rotundifolia Banks f. beckettii Boivin, Nat. can. 87: 42. 1960
Canada: Manitoba, 3 mi. S of Churchill, E. Beckett 111, 12 July 1954, Holotype
Orcuttia californica Vasey var. viscida Hoover, Bull. Torrey Bot. Club 68: 155. 1941
U.S.A.: California, Sacramento Co., S of Folson, B. Crampton 5005, 7 July 1958, Topotype
Orcuttia greenei Vasey, Bot. Gaz. 16: 146. 1891
U.S.A.: California, Butte Co., 10 mi. SE of central Chico, B. Crampton 5069, 12 Aug. 1958, Topotype
Orcuttia inequalis Hoover, Madrono 3: 229. 1936
U.S.A.: California, Stanislaus Co., Montpellier, R.F. Hoover, 22 July 1935 (Amer. Gr. Nat. Herb. 1538), Topotype
Oreocarya flava A. Nels., Bull. Torrey Bot. Club 25: 202. 1898
U.S.A.: Wyoming, Sweetwater Co., Red Desert near Point of Rocks, A. & R. Nelson 785, 15 June 1933, Topotype
Oreocarya paradoxa A. Nels., Bot. Gaz. 56: 69. 1913
U.S.A.: Colorado, Montrose Co., Paradox Valley, W.A. Weber, 31 May 1960, Topotype
Ornithogalum degenianum Polgar, Magy. Bot. Lapok 27: 20. 1928
Hungary: Papakovacsi, Polgar & Javorka (Fl. Hung. ex. 992), 4 May 1930, Topotype
Ornithopus ebracteatus Brot., Fl. Lusit. 2: 159. 1804
Portugal: Coimbra, W. Rothmaler, 5 May 1936, Topotype
Orobanche brassicae Novopokr., Bull. Don. Inst. Agric. Novotcherkask 8: 54. 1928
U.S.S.R.: Prov. Rostov, prope stationem Persianovka, I. Novopokrovsky, (Fl. ex USSR 3489), 10 Aug. 1928, Isotype
Orobanche corymbosa (Rydb.) Ferris ssp. mutabilis Heckard
Canada: British Columbia, about three miles west of Lumby, Calder & Savile 10948, 24 July 1953, Paratype; Munson Mountain about one mile northeast of Penticton, Calder & Savile 10226, 8 July 1953, Paratype; along trail to Ashnola Range, 49°07'N 120°08'W, Calder et al. 19812, 5 Aug. 1956, Paratype
Orobanche corymbosa (Rydb.) Ferris ssp. mutabilis Heckard, Can. J. Bot. 56: 187. 1978
Canada: British Columbia, about half a mile along Nickel Plate road from junction SE of Hedley, Calder & Savile 10726, 19 July 1953, Paratype
Orobanche ludoviciana Nutt. f. albinea Boivin, Phyt. 22: 347. 1972
Canada: Saskatchewan, Maple Creek District, Val Marie, Boivin & Alex 9870, 22 juillet 1952, Holotype
Orobus pannonicus Jacq., Enum. Stirp. Pler. 128. 1762
Austria: prope Vindobonam, Wiesbaur, Topotype
Orthocarpus barbatus Cotton, Bull. Torrey Bot. Club 29: 574. 1902
U.S.A.: Washington, Grant Co., Coulee City in Grand Coulee, J.W. Thompson 11660, 16 June 1935, Topotype
Orthocarpus brevistylis Hoover
U.S.A.: California, San Luis Obispo County, west edge of Carrizo Plain on Highway 58, R.F. Hoover 10,362, 5 April 1967, Paratype
Orthocarpus brevistylis Hoover, Four Seasons 2(4): 14-15. 1968
U.S.A.: California, San Luis Obispo Co., north side of lower Cuyama Valley, R.F. Hoover 8119, 19 Apr. 1982, Isotype
Orthocarpus erianthus Benth. var. gratiosus Jepson & Tracy in Jepson Man. Fl. Pl. Calif. 941. 1925
U.S.A.: California, Humbolt Co., Bucksport, near Eureka, J.P. Tracy 17465, 14 May 1944, Topotype
Orthocarpus faucibarbatus Gray var. albidus Keck, Madrono 5: 164- 165. 1940
U.S.A.: California, Humboldt Co., Humboldt Bay, 4 miles south of Eureka, Keck & Clausen 3380, 16 June 1935, Paratype
Oryzopsis hymenoides (Roem. & Schult.) Ricker X Stipa neomexicana (Thurb.) Scribn. hybr. nov. Weber, Rhodora 59: 273-277
U.S.A.: Colorado, Boulder County, 6 miles north of Boulder along foothills road, 26 June 1957, W.A. Weber 10565, Isotype
Oryzopsis swallenii C.L. Hitchc., Brittonia 20: 164. 1968
U.S.A.: Idaho, Clark Co., NW of Blue Dome, C.L. Hitchcock 23868, 7 July 1965, Isotype
Osmanthus didymopetalus P.J. Green, Notes Royal Bot. Gard. Edinb. 22: 536. 1958
China: Hainan, H.Y. Liang 63771, 23 Oct. 1923, Paratype
Osmorhiza obtusa(Coulter & Rose) Fern. var. cupressimontana Boivin, Can. Field-Nat. 65: 20. 1951
Canada: Saskatchewan, Cypress Hills Park, A.J. Breitung 4742, 13 July 1947, Holotype
Osteomeles intermedia Pittier, Contr. U.S. Natl. Herb. 20: 107. 1918
Columbia: Santa Marta, H.H. Smith 1751, 1898-1901, ? Isotype
Ostrya knowltonii Coville, Gard. & For. 7: 114 f. 23. 1894
U.S.A.: Arizona, Grand Canyon, W.R. Dudley, June 1904(?), Topotype
Ostrya virginiana (Mill.) Koch var. lasia Fernald, Rhod. 38: 414. 1936
U.S.A.: Florida, Columbia Co., Lake City, G.V. Nash 2158, 11-19 July 1895, Isotype
Oxytheca watsonii Torrey & Gray in S. Watson, Bot. King's Expedition, p. 311. 1871
U.S.A.: Nevada, Monitor Valley, Holmgren & Reveal 1500, 2 Aug. 1964, Topotype
Oxytropis arctica R.Br. in Parry 1st Voy. App. 278. 1824
Canada: District of Franklin, Melville Island, Mosquin & Martin 6481, 27 July 1965, Topotype
Oxytropis chartacea Fassett, Rhod. 38: 95. 1936
U.S.A.: Wisconsin, Plainfield, N.C. Fassett 16704, 15 Sept. 1935, Isotype
Oxytropis Columbiana St. John, Proc. Biol. Soc. Wash. 41: 100. 1928
U.S.A.: Washington, Stevens Co., Columbia River at Marcus, H.T. Rogers 543, 25 May 1940, Topotype
Oxytropis deflexa (Pall.) DC. var. capitata Boivin, Sv. Bot. Tid. 56: 499-500. 1963
Canada: Ontario, 34 mi. sud du cap Henriette, 54º40'N, Dutilly & Lepage 31367, 17 août 1953, Holotype
Oxytropis deflexa (Pallas) DC var. parviflora Boivin
Canada: Mackenzie, Norman Wells, Cody & Gutteridge 7447, 7811, 22 July 1953, 5 Aug. 1953, ParatypeS; Seven Mile Lake, 60°02'N 112°38'W, Cody & Loan 4676, 22 July 1950, Paratype; Cody 4454, 16 July 1950, Paratype; Yellowknife, Cody & McCanse 2717, 19 July 1949, Paratype; Yukon, Whitehorse, Gillett & Mitchell 3252, 9 June 1949, Paratype; Ear Lake near Whitehorse, Gillett & Mitchell 3650, 9 July 1949, Paratype; Whitehorse, 60°43'N 135°03'W, Gillett & Mitchell 4424, 11 Aug. 1949, Paratype; Dawson, Calder & Billard 3207, 20 June 1949, Paratype; Dawson, Calder & Billard 3377, 29 June 1949, Paratype; Dawson, Calder & Billard 3737, 16 July 1949, Paratype; north end of Marsh Lake, 60°33'N 134°30'W, Calder & Gillett 26461, 4 July 1960, Paratype; north end of Marsh Lake, J.A. Calder 28336, 17 Aug. 1960, Paratype; north end of north Von Wilczek Lake, Calder & Kukkonen 28080, 10 Aug. 1960, Paratype; NW of Destruction Bay on Kluane Lake, 61°19'N 138°56'W, Calder & Kukkonen 28196, 13 Aug. 1960, Paratype; Tatchun River, 62°07'N 136°18'W, Calder & Gillett 25823, 22 June 1960, Paratype; 8 miles north of Carcross, 60°16'N 134°44'W, Calder & Kukkonen 28308, 15 Aug. 1960, Paratype; 3 miles northeast of Mayo, 63°36'N 135°53'W, Calder & Gillett 4104, 1 Aug. 1949, Paratype; Lower Lebarge Station on Lewes River, 61°23'N 135°13'W, Gillett & Mitchell 3945, 24 July 1949, Paratype; Mile 85 from Alaska Highway on road to Dawson, 61°52'N 136°07'W, Calder & Gillett 25794, 22 June 1960, Paratype; Alberta, about 12 miles north of Jasper, J.A. Calder 23924, 22 July 1959, Paratype; Jasper, E.H. Moss 4842, 6 July 1939, Paratype; Grande Prairie, J. Bostock s.n., Aug. 1926; Paratype; Peace River, Groh 2774, 16 Aug. 1946, Paratype; Prestville, E.H. Moss 7591, 28 July 1947, Paratype; Hines Creek, H. Groh 995, 15 Sept. 1939, Paratype; British Columbia, on road Riske Creek to Hanceville, 51°58'N 122°38'W, Calder et al. 18285, 3 July 1956, Paratype; One Eye Lake, Calder et al. 18629, 10 July 1956, Paratype; Prince George, Groh 623, 17 Aug. 1939, Paratype; Pouce Coupe, Groh 3081, 5 Sept. 1946, Paratype; near mouth of Halfway River, 56°13'N 121°27'W, Calder & Kukkonen 27054, 15 July 1960, Paratype; Route de l'Alaska, Calder & Kukkonen 27602, 27295, 26640, July 1960, Paratypes
Oxytropis deflexa (Pall.) DC. var. parviflora Boivin, Sv. Bot. Tid. 56: 498. 1963
Canada: Alberta, 1 mile SW of Fort Smith, N.W.T., Cody & Loan 4496, 17 July 1950, Holotype
Oxytropis foliolosa Hook., Fl. Bor. Am. 1: 146. 1831
Canada: Alberta, Fort Saskatchewan, G.H. Turner 2465, 6 June 1941, Topotype
Oxytropis ircutensis M. Pop., Herb. Fl. SSSR ex. 3835
U.S.S.R.: Prov. Irkutsk, pagum Vvedenskoë, Popov & Andreeva, 28 May 1952, Isotype
Oxytropis johannensis (Fernald) Fernald f. bicensis Vict. & Rousseau, Contr. Inst. Bot. Univ. Montreal 36: 32. 1940
Canada: Quebec, Montagne de Bic, J. Rousseau 50297, 15 juillet 1936, Isotype
Oxytropis lambertii Pursh f. canadensis Gaudin, Bull. Soc. Bot. France 48: xvi. 1902
Canada: Manitoba, Portage-la-Prairie, I.K. McMorine Aug. 1897, Type Collection Material
Oxytropis leucantha (Pallas) Pers. var.magnifica Boivin
Canada: Alberta, Macleod District, R.H. Dixon 1632, 2 June 1940, Paratype
Oxytropis leucantha (Pallas) Pers. var. hudsonica (Greene) Boivin f. galactantha Boivin, Nat. can. 94: 76. 1967
Canada: Franklin District, Melville Peninsula, Repulse Bay, P.F. Bruggeman 52, 27 July 1950, Holotype
Oxytropis leucantha (Pallas) Pers. var. leuchippiana Boivin, Nat. can. 94: 76. 1967
Canada: Yukon, Whitehorse, Gillett & Calder 3181, 4 June 1949, Holotype
Oxytropis leucantha (Pallas) Pers. var. magnifica Boivin, Nat. can. 94: 77. 1967
Canada: Alberta, High River, J. Fletcher, 27 June 1902, Holotype & Isotype
Oxytropis mazama St. John, Proc. Biol. Soc. Wash. 41: 101-102. 1928
U.S.A.: Washington, Rainier National Park, Mt. Wow, J.W. Thompson 12578, 15 Aug. 1935, Topotype
Oxytropis nigrescens (Pall.) Fisch. var. bryophila (Greene) Lepage f. albida Lepage, Amer. Midl. Nat. 46: 758. 1952
U.S.A.: Alaska, Kodiak, E. Lepage 25089, 24 June 1949, Isotype
Oxytropis nigrescens (Pall.) Fisch. var. lonchopoda Barneby, Leafl. West. Bot. 10: 23. 1963
Canada: Yukon, Ogilvie Mts., Cathedral Rocks, 66º02'N 138º44'W, Calder & Gillett 26013A, 29 June 1960, Holotype
Oxytropis obnapiformis Porter, Madrono 9: 133. 1947
U.S.A.: Colorado, Moffat Co., Maybell, Porter 3616, 2 June 1950, Paratype
Oxytropis pyrenaica Gren. & Godr., Fl. Fr. 1: 449. 1848
France: Hautes Pyrénées, Gavarine, W.E. Nicholson, Aug. 1902, Topotype
Oxytropis roaldii Ostenf. in Vid.-Selsk. Skr., Christiania Math.-Nat. No. 8: 54. 1909
Canada: Yukon, Herschel Island, J.V. Matthews, 31 July 1983, Topotype
Oxytropis scammaniana Hultén, Ark. Bot. 33B: 4. 1947
U.S.A.: Alaska, Eagle Summit, E. Lepage 25380, 7 Aug. 1949, Topotype
Oxytropis tananensis Jurtz, Russian Acad. Sc. 78(9): 61-62. 1993
Canada: Yukon, Tantalus Butte at Carmacks, 62º07'N 136º16'W, Calder & Kukkonen 27976, 9 Aug. 1960, Paratype
Oxytropis viscida Nutt. ex T. & G., Fl. N. Amer. 1: 341. 1838
U.S.A.: Wyoming, Fremont Co., Beaver Hill west of the Sweetwater Crossing on the Oregon Trail, C.L. Porter 6809, 2 Aug. 1955, Topotype