362 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
17. Trifolium procumbens L. Sp. Pl. 2: 772. 1753. 
Type Locatitry: European. 
SPECIMENS EXAMINED: Seattle, Piper, July, 1895; Suksdorf 1804; Tacoma, Leckenby, 
May, 1898. 
18. Trifolium dubium Sibth. Fl. Oxon. 231. 1794. 
Trifolium minus Smith, Engl. Bot. pl. 1256. 1799. 
Type Locatity: Near Oxford, England. 
SPECIMENS EXAMINED: Chenowith, Suksdorf 2585. 
19. Trifolium flavulum Greene, Pittonia 2: 223. 1892. 
Tyre Locauiry: Western California. 
Rance: Western California. 
SPECIMENS EXAMINED: Port Ludlow, Binns, May 25, 1890; Whatcom, Suksdorf 1802; 
Seattle, Piper in 1889. 
These are probably all introduced from California. 
20. Trifolium fimbriatum Lindl. Bot. Reg. 18: pl. 1070. 1827. 
Trifolium spinulosum Dougl.; Hook. Fl. Bor. Am, 1: 133. 1830. 
Trifolium heterodon Torr. & Gr. Fl. 1: 318. 1838. 
Type Locatity: Columbia River. Collected by Douglas. 
Rance: British Columbia, Washington, Oregon, and Idaho. 
SPECIMENS EXAMINED: Grays Harbor, Lamb 1165; Westport, Henderson, June 25, 1892; 
North Yakima, Mrs. Steinweg, Henderson; Spokane, Piper, Sa ndberg, Heller, & MacDougal 
1028; Marshall Junction, Piper; Clallam County, Elmer 2539; Coupeville, Gardner 70; 
Seattle, Piper 2761; Smith 473; Henderson 2329; Olympia, Henderson 2329 ; Muckleshoot, 
Dr. Ruhn; Spangle, Suksdorf 272; Medical Lake, Henderson 2330; Walla Walla, Lyall in 
1860; without locality, Cooper in 1854; waco, Piper 4989. 
The Californian T. wormskioldii Lehm. is distinguished by its less deeply lobed 
involucre. 
ZONAL DISTRIBUTION: Transition. 
21. Trifolium tridentatum Lindl. Bot. Reg. 13: under pl. 1070. 1827. 
Tyre Locatity: Columbia River. Collected by Douglas. 
Range: Vancouver Island to California in the coast region, 
SPECIMENS EXAMINED: Clallam County, Elmer 2536; Lopez Island, Lyall in 1858-59; 
Coupeville, Gardner 71; Tacoma, Flet 903; Fourth Plain, Piper 3073; Rock Island, 
Henderson; Vancouver, Piper 4933. 
ZONAL DistRipuTION: Humid Transition. 
22. Trifolium oliganthum Steud. Nom. ed. 2. 2: 707. 1841. 
Trifolium pauciflorum Nutt.; Torr. & Gr. Fl. 1: 319. 1838, not Urv. 1822. 
Tyre Locaxity: ‘Wet places on the higher plains of the Oregon, particularly abundant 
near the outlet of the Wahlamet.” Collected by Nuttall. 
Range: Vancouver Island to California in the coast region. 
SPECIMENS EXAMINED: Lopez Island, Lyall in 1858; Seattle, Piper 727; Tacoma, Flett 
904, 188; Rock Island, Henderson, July, 1892. 
ZONAL DisTRIBUTION: Humid Transition. 
23. Trifolium variegatum Nutt.; Torr. & Gr. Fl. 1: 317. 1838. 
Trifolium melananthum Hook. & Arn. Bot. Beech. Voy. 331. 1839. 
Tyre Locauity: ‘‘Springy places near the mouth of the Wahlamet,”’ Oregon. Col- 
lected by. Nuttall. 
Rance: British Columbia to California and Idaho. 
SPECIMENS EXAMINED: Coupeville, Gardner 68; Seattle, Piper in 1888; Smith; Olympia, 
Henderson 2327, 2328; west Klickitat County, Suksdorf 2580; Fort Vancouver, Tolmie (2); 
Yakima County, Suksdorf 273; Yakima, Watt; Ellensburg, Whited 491; Elmer 402; Egbert 
