136. LEGUMINOS#.. TRIFOLIUM. 
cles axillary: flowers sessile or nearly so, never reflexed: pods 
often dehiscent at the ventral suture: veins of the leaves often 
reticulate. 
* Jnvolucre not membranaceous, deeply lobed, the lobes laciniately 
and sharply toothed: corolla not becoming inflated. 
T. fimbriatum Lindl. Bot. Reg. t. 1070. Glabrous: stems long and 
thick, prostrate: stipules ovate, acuminate, laciniate-spinulose : leaflets ob- 
long or slightly cuneate, spinulose-denticulate, an inch or more long: in- 
voluere laciniately many-cleft, shorter than the large subglobose heads of 
purple or reddish flowers : teeth of the calyx broadly subulate, straight, 
half the length of the corolla, shorter than the tube, unequal, spiny: cor- 
olla slender: pod 2-seeded. In salt marshes along the coast, Oregon to 
California. ! 
T. spinulosum Dougl. Hook. Fl. i, 138, Glabrous: stems prostrate or 
ascending, slender, 1-2 feet long: stipules ovate, acuminate, spinulose- 
serrate; leaflets oblong, acute at each end, spinulose-denticulate, termi- 
nated by a rigid spiny point; involucre often small, laciniately mauy-cleit, 
shorter than the subglobose heads; teeth of the calyx narrowly subulate, 
pungent, shorter than the corolla, 3-4 times as longas the tube; corolla 
white, or the keel and wings tipped with fine purple: pods 2-seeded. In 
mountain valleys near springs, Oregon. 
T. heterodon T. & G. FI. i, 133. Glabrous: stems several from a 
branching perennial root, decumbent, 10-18 inches long, simple or a little 
branched, usually produging only terminal heads: stipules membrana- 
ceous, ovate, acuminate, laciniately serrate with subulate teeth, the lower 
ones lanceolate and nearly or quite entire; leaflets oblong or oval; some- — 
what cuneiform at base, mucronately ciliate-serrulate, obtuse, the totver- 
most mostly emarginate, 6-i8 lines long: heads an inch or more in diam- 
eter. depressed-globose, long-peduncled ; involucre large, foliaceous, lacini- 
ately many-cleft with spinulose lobes, little shorter than the heads; teeth 
of the calyx narrowly subulate, nearly equal, 2-3 times longer than the 
tube, shorter than the corolla; petals an inch long, purple, the upper one ~ 
pale at the tip: pods somewhat stipitate, 3-6-seeded. In salt meadows 
along the coast, near the mouth of the Columbia river. / 
T. obtusiflorum Hook. Ic. Pl. t. 218. Sparsely short-hairy or glabrous, 
often more or less resinous-glandular: stems stout, a few inches to 3 feet 
long, from an annual root, erect or decumbent, diffusely branched: lower 
stipules scarious, prominently nerved, lanceolate, setaceously acuminate, 
an inch. long, entire or toothed, upper ones more herbaceous, setaceously 
pectinate: leaflets elliptic-lanceolate 12-18 lines long, spinulose-serrate, 
acute at each end, terminated by a rigid spiny point: heads an inch or 
more broad on long stoutish peduncles: inyolucre setaceously many-cleft ; 
tube of the calyx oblong-campanulate, 3 lines long, with 10 prominent and 
as many lesser nerves, these branching and forming reticulations above, 
teeth subulate-spinose, entire, shorter than the tube; petals 8-10 lines 
long, lilac-purple with dark centre: pods elliptical, 2-seeded, dehiscent. 
On clayey hillsides, southwestern Oregon to middle California. AG 
'. tridentata Lindl. Bot. Reg. under t. 1070. Glabrous annual: stems 
slender, erect, simple or branched, 3-20. inches high: stipules searious, 
narrowly lanceolate, spinulose acuminate, the lower entire, the upper seta- 
ceously laciniate: leaflets linear-lanceolate, 1-2 inches long, spinulose ser- 
rate; heads nearly an inch broad: involucre orbicular, setac: ously many- 
lobed and toothed, shorter than the flowers: tube ot the calyx campann- 
late, prominently 10-nerved, reticulated, the short oblong lobes abruptly 
contracted above to a slender spine, often subtended by a pair of short 
spines or teeth; flowers purlpe and white: mature peds fully as broad as 
