Trifolium. LEGUMINOS^E. 



19. T. monanthum, Gray. Still more slender, one to four inches high, usually 

 sparingly villous with long scattered hairs, decumbent : stipules lanceolate, entire or 

 nearly so ; leaflets obcordate to oblanceolate, one to four lines long, mostly retuse, 

 sparingly toothed : heads 1 4-flo\vered ; involucre very small, 2-3-parted and usu- 

 ally unilateral : flowers 4 to 6 lines long, white or purplish, much exceeding the 

 short calyx : calyx-teeth subulate, shortly acuminate, thin. Proc. Am. Acad. vi. 

 523. T. pauciflorum, var. (?) parvum, Kellogg, Proc. Calif. Acad. v. 54. 



On moist sunny slopes in the Sierra Nevada ; on the Upper Tuolunine, at 8,900 feet altitude, 

 and at the head of the South Fork of King's Eiver (Brewer) ; Yosemite Valley (Gray) ; at Cisco 

 (Kellogg) ; Lassen's Peak, Lemmon. Also in the mountains of Nevada, Wtiecler. 



* * Involucre membranaceous, at least at base, less deeply lobed ; the lobes entire 



or toothed: corolla not becoming inflated. 



20. T. microcephalum, Pursh. Villous with soft hairs, slender, erect or 

 decumbent : stems often a foot or two long : stipules ovate to lanceolate, acuminate, 

 mostly entire ; leaflets oblanceolate to obovate, usually retuse, serrulate : heads 

 small, dense ; involucre about 9-lobed, the lobes acuminate, 3-nerved, entire : calyx 

 hairy ; its teeth subulate, with a broad scariously margined sometimes toothed base, 

 attenuate to a long spinulose apex, nearly equalling the white or light rose-colored 

 corolla : ovules two : pod globose, 1-seeded. Torr. & Gray, Fl. i. 317. 



Common on hillsides and the sandy beds of dry creeks, chiefly in the Coast Ranges, from Puget 

 Sound to Southern California ; Guadalupe Island (Palmer) ; Northern Nevada, Watson. 



21. T. microdon, Hook. & Arn. Kesembling the last : involucre broader, 

 nearly enclosing the head ; its lobes about 3-toothed : calyx smooth, angled ; the 

 teeth rigid, broadly triangular, acute, with a narrow scarious serrulate margin. 

 Bot. Beechey, 330, t. 79 ; Torr. & Gray, Fl. i. 691. 



From about San Francisco northward ; Washington Territory, Lyall, Hall. Also Chilian. 



22. T. cyathiferum, Lindl. Smooth : stems erect or ascending, a foot high 

 or less : stipules ovate to lanceolate, laciniately toothed ; leaflets oblanceolate to 

 obovate, obtuse or acute, a half to an inch long : heads larger ; involucre conspic- 

 uous, very broad and meinbranaceous, with short many-nerved and toothed lobes : 

 calyx strongly 5-uerved, membranaceous and somewhat inflated ; the nerves excur- 

 rent above and setaceously branched, equalling the short rose-colored corolla : pod 

 2-seeded. Bot. Eeg. xiii, under t. 1070 ; Hook. Fl. i. 133, t. 50. 



Sierra Valley, Sierra Co. (Lemmon) ; Northern Nevada (Anderson, Watson) ; and northward to 

 the Columbia River. A remarkable species. 



* * * Standard becoming conspicuously inflated and enclosing the rest of the flower : 



involucre nearly obsolete in T. depauperatum. 



+ Heads mostly large : involucre conspicuous. 



23. T. barbigerum, Torr. Somewhat pubescent : stems rather stout, decum- 

 bent or ascending, a span high or less : stipules scarious, broadly ovate, laciniate ; 

 leaflets obovate or ovate-oblong, obtuse or retuse, half an inch long or less : invo- 

 lucre as broad as the heads (4 to 8 lines wide), shortly lobed and setaceously many- 

 toothed : calyx-tube short, membranaceous ; its teeth setaceously awned, plumose, 

 the lower usually exceeding the purple corolla, sometimes 2-3-parted: pod 2-seeded. 



- Pacif. E. Rep. iv. 79. 



Var. Andrews!!, Gray. A stout villous form ; the heads larger, sometimes an 

 inch broad : calyx-teeth very long. Proc. Am. Acad. vii. 335. 

 Near the coast from Monterey to Mendocino County ; very variable. 



24. T. fucatum, Lindl. Smooth : stems stout and succulent, a foot or two 

 high or more : stipules large and scarious, usually very broad and entire ; leaflets 

 obovate, often large ( to 1 inches long), obtuse: heads large; involucre broad, 



