308 LEGUMINOS^. 



nate; raehis prolonged through the head as steraile point ahout 3 hnes 

 long; flowers 3 or 3J lines long; calyx-teeth suhulate, three times as 

 long as the tube; corolla reddish or deep purple, the ends of the petals 

 more or less definitely white-tipped; pod exserted, 2-seeded; seed 

 obliquely oval, straw-colored. 



Common on low hills and in valleys: Los Angeles and San Luis 

 Obispo Cos. northward through the Coast Kange region (Alameda, 

 San Francisco, Napa Valley, Solano Co., etc.), ranging beyond the 

 northern boundary of California. Apr.-May. 



10. T. microdon H. & A. Stems erect or decumbent, stoutish. 

 8 to 16 in. long, faintly pubescent; leaflets broadly obcordate, serru- 

 late, 6 lines long; heads 4 lines broad; involucre 12 to 15-lobed, the 

 lobes 3 to several-toothed and spreading abruptly from the head after 

 anthesis; calyx-teeth short, i or J the length of the tube; corolla 

 white, fading pinkish. 



Plains of the San Joaquin and Sacramento; valleys of the Coast 

 Eanges (Alameda Co., Mt. Tamalpais, Napa Valley and north- 

 ward). Apr. 



11. T. microcephalum Pursh. Stems slender, erect or decum- 

 bent, 3 in. to even 2 ft. long; herbage soft-pubescent; leaflets obovate, 

 serrulate, notched at apex, stipules ovate, acuminate; heads 3 lines 

 broad; involucre about 9-lobed, the lobes erect, acuminate, cuspidate, 

 entire, 3-nerved; calyx-teeth longer than the tube, spinulose at apex, 

 margined at base with a broad often denticulate or scarious border 

 which is more or less protruded; corolla white or light rose-color, 

 scarcely exceeding the calyx-teeth; pod globose, 1-seeded. 



Hillsides and valleys: North Coast Ranges (Vacaville and St. 

 Helena) southward to San Francisco, Paciflc Grove and Southern 

 California. Apr. 



12. T. variegatum Nutt. Glabrous annual; stems slender, decum- 

 bent or ascending; leaflets obovate to oblong-oblanceolate, obtuse or 

 retuse, spinulose-serrulate, 4 to 10 lines long; stipules oblong- or 

 ovate-lanceolate, sharply toothed or laciniate; peduncles slender, 

 longer than the leaves; involucre laciniate, shorter than the heads; 

 heads small (3 to 15-flowered and J in. broad or less); calyx-tube 

 15-nerved, its teeth subulate-setaceous, entire, shorter than the deep 

 purple or whitish corolla but longer than the tube; pod 2-seeded. 



Common in low moist ground, throughout California. Apr.-May. 

 Greene has a var. melananthum, the calyx-teeth more triangular and 

 only pungently acute or acuminate and of a dark purple almost to 

 the base; and also a var. major, very large, stout and fistulous, with 

 cuneate-oblong leaflets, heads 1 in. broad, and petals purple with 

 white tips. 



13. T. ollganthum Steud. Pale green, glabrous annual; stems 

 erect, very slender, simple or with a few ascending branches, 7 to 15 

 in. high; upper leaflets linear, acute, f to 1 in. long, spinulose- 

 serrate or nearly entire; lower leaflets cuneate-oblong or -obovate, 2 

 or 3 lines long; petioles very slender; stipules lanceolate, laciniate; 



