trifolium. LEGUMINOS^E. 135 



pods 1-2-seeded, a little longer than the calyx, dehiscent. Along streams 

 and ditches, Siskiyou Mountains, Oregon and northern California, 



* * * * Peduncles axillary : flowers on slender pedicels, soon re- 

 flexed: ovules 2-4: spreading perennials. 



T. Breweri Watson 1. c. xi, 131. Somewhat pubescent throughout, 

 stems procumbent, very slender, 4-12 inches long, from a rather thick 

 perennial root: stipules lanceolate, short; leaflets obovate to oblong, 

 mostly refuse, toothed or serrulate, 3-9 lines long: flowers white or pink- 

 ish, on slender pedicels, in loose globose heads: calyx very narrow, the 

 slender teeth much shorter than the corolla. In moist places, south- 

 western Oregon and northern California. 



T. repexs L. Sp. 1080. (White Clover). Glabrous perennial; stems 

 slender, creeping, rooting at all the nodes, 4-20 inches long: leaves long- 

 petioled; stipules narrowly lanceolate, scarious ; leaflets obcordate, den-* 

 tieulate, 4-10 lines long: flowers white or pinkish, in loose depressed-glo- 

 bose long-peduncled heads, soon reflexed ; teeth of the calyx unequal, 

 lanceolate-subulate, shorter than the tube: pods 4-seeded. Common in 

 cultivated fields and roadsides. Introduced from Europe. 



***** Peduncles axillary: flowers on short pedicels, in small 

 heads, at length reflexed : teeth of the calyx subulate, mostly glabrous : 

 slender annuals. 



T. ciliolatum Benth. PI. Hartw. 304. T. ciliatum Nutt. not Clark. 

 Glabrous; stems erect, often 1-2 feet high, simple or branched: stipules 

 usually narrow, acuminate ; leaflets cuneate-oblong to obovate, 6-12 lines 

 long, obtuse or retuse, serrulate : flowers in small dense ovate heads, the 

 rach is prolonged above as 2 stout bristle : calyx campanulate, the teeth 

 very unequal, the two upper ones lanceolate, spinulose-acuminate, longer 

 than the corolla, the others similar but smaller, about two-thirds as long, 

 all with scarious and rigidly ciliolate margins; petals purple and white, 

 3-4 lines long, the upper one free and folded around the others: pods 

 shorter than the calyx, 1-seeded; seeds oblong, turgid, light brown. In 

 moist meadow r s of the Willamette Valley to California. 



T. Hallii. T. grdcilentum and bifidum of authors as to the Oregon plant 

 not T. & G. Sub villous to glabrous, pale green and somewhat glaucous : 

 stems slender, diffusely branched to simple, 0-18 inches high from a slen- 

 der annual root: stipules ovate-lanceolate, setaceous-acuminate, entire : 

 leaflets linear-cuneate to obcordate, sparsely dentate, more or less deeply 

 notched at the apex, the midnerve excurrent in the centre, 4-8 lines long: 

 peduncles exceeding the leaves, pilose near the summit; flowers pink or 

 rose-color, in small depressed-globose 10-30-fllowered heads, on short pedi- 

 cels, soon reflexed;* calyx 5-parted, the teeth subulate-setaceous, sparsely 

 hirsute, somewhat unequal, but little shorter than the corolla; petals rose- 

 color, 3-4 lines long, the upper one free and folded over the others : pods 

 included, 1-seeded. Open places and prairies, western Washington to 

 California. 



T. PBOCUMBENS L. Sp. 772. Pubescent; stems procumbent to sub-erect, 

 slender, 4-12 inches long: leaves short-petioled, pinnately-trifoliolate ; 

 stipules rather foliaceous, ovate, ciliate, mostly shorter than the petiole; 

 leaflets cuneate-obcordate or cuneate-oblong and emarginate, denticulate, 

 the lower pair distant from the terminal one: flowers on slender axillary 

 peduncles, in small ovate heads, soon reflexed ; teeth of the calyx un- 

 equal, the two upper ones very short; petals yellow, the upper one striate 

 when old: pods 1-seeded. Common in fields and roadsides. Introduced 

 from Europe. 



§ 3. Involucrarium T .& G. FL i, ol7. Heads of flowers sub- 

 tended by a monophylloue^ usually many-cleft involucre: pedun- 



