PIPER FLORA OF THE STATE OF WASHINGTON. 363 



Springs, Sandberg & Leiberg 401; Wilson Creek, Lake cfe Hull 435; Spokane, Piper; Spo- 

 kane County, SuJcsdorf 2581 ; Meyers Falls, Kreager 504; Prosser, Cotton 737, 810; without 

 locality, Vasey in 1889. 



Zonal distribution: Upper Sonoran and Transition. 



24. Trifolium cyathiferum Lindl. Bot. Reg. 13: under pi. 1070. 1827. 

 Type locality: " Columbia River. " Collected by Douglas. 



Range: British Columbia to Idaho and north Caliiomia. 



Specimens examined: Klickitat County, Suksdorf 9; Klickitat River, Flett 1263a 

 junction Crab and Wilson creeks, Sandberg cfc Leiberg 303; Spokane County, Suksdorf 2584 

 Pullman, Piper 1484; Clealum, Henderson, June, 1892; Wilson Creek, Lake & Hull 433 

 Blue Mountains, Horner 316. 



Zonal distribution: Arid Transition. 



25. Trifolium microdon Hook. & Arn. Hook. Bot. Misc. 3: 180. 1833. 

 Type locality: Valparaiso, Chile. 



Range: Vancouver Island to California. Chile. 



Specimens examined: Oyhut, Lamb 1266; Bellingham Bay, Suksdorf \&)^; Alki Point, 

 Piper in 1889; Port Ludlow, Binns; Cascade Mountains, latitude 49°, Lyall; Ilwaco, Piper 

 4994, 4961. 



Zonal distribution: Humid Transition. 



26. Trifolium microcephalum Pursh, Fl. 2: 478. 1814. 



Type locality: "On the banks of Clark's River." Collected by Lewis. The exact 

 spot is on the Bitter Root River, Montana, near the mouth of the Lolo. 



Range: British Columbia to west Montana and California. 



Specimens examined: Whidby Island, Gardner 69; Puget Sound, Suckley; Everett, 

 Piper, July, 1892; Tacoma, Flett 905; Charleston, Piper, July, 1895; W^oodlawn, Hender- 

 son, June, 1892 ; Ellensburg, Elmer 404 ; Egbert Springs, Sandberg cfe Leiberg 421 ; Muckle- 

 shoot. Dr. iJu^n; Wilson Creek, Lake cfe Hidl 434; Spokane, Piper, July, 1896; Dewart in 

 1900; Henderson, July, 1892; Spangle, Suksdorf 17 A; Coppei River, Homer 597; without 

 locality, Vasey in 1889; Clarks Springs, Kreager 138; Fort Vancouver, Scouler. 



Zonal distribution: Transition. 



MEDICAGO. 



Annual ; flowers yellow. 



Pod, 1-seeded, black, reticulate \. M. lupulina. 



Pod several-seeded, twisted, spiny on the edge 2. M. denticulata. 



Perennial ; flowers violet. , 3. Jf . sativa. 



1. Medicago lupulina L. Sp. PI. 2: 779. 1753. Yellow trefoil. 

 Type locality: European. 



Specimens examined: Fairhaven, Piper, July, 1897; Seattle, Piper, July, 1895; Bin- 

 gen, Suksdorf 2587; Walla Walla, Leckenby, May, 1898. 



2. Medicago denticulata Willd. Sp. PI. 3: 1414. 1803. Bur clover. 

 Type locality: None cited. 



. Specimens examined: Whatcom, Suksdorf 1806; Tacoma, Flett 52; Seattle, Piper in 

 1888. 



3. Medicago sativa L. Sp. PI. 2: 778. 1753. Alfalfa. 

 Type locality: "Habitat in Hispaniae, Galliae apricis." 



Abundantly cultivated, especially in eastern Washington, and a frequent escape. 



PSORALEA. 



Leaflets broadly ovate I. P. physodes. 



Leaflets lanceolate 2. P. lanceolata. 



