LEGUMINOS^. 75 



rugose ; style filiform, as long as the legume ; seeds unequally cordate. 

 TrifoUum officinale, var, a. Linn. 



Fields. Can. to Geor. Aug. Q.—Stem 2—4 feet high. Flowers in long ra- 

 cemes, yellow. Plant giving out an odor when dry, similar to the vernal grass. 

 Introduced from Europe. Yellow Melilot. 



2. M. leucantha D. C. : stem erect, branched ; leafets ovate-oblong, 

 truncate and mucronate at the apex, remotely serrate ; stipules setaceous ; 

 teeth of the calyx unequal, as long as the tube ; standard longer than the 

 keel and wings ; legume 1 — 2-seeded, ovate, lacunose-rugose, green ; seeds 

 exactly ovate. M. vulgaris Willd. Enum. TrifoUum officinale, var. b. 

 Linn. 



Fields. N. S. July, Aug. ^.—Stem 3—5 feet high. Flowers white. Ra- 

 cemes longer and less crowded than in the former. Both species become fragrant 

 upon drying. Introduced. White Melilot. Scented Clover 



6. TRIFOLIUM. Tourn.— Clover Trefoil. 

 (From the Latin ires, three ; and folium, a leaf) 



Calyx tubular, persistent, without glands, 5-cleft or 5-tootlied. 

 Segments subulate. Keel shorter than the wings and standard. 

 Stamens diadelphous. Legume small, scarcely dehiscent, often 

 ovate, 1 — 2-seeded, as long as the calyx and covered by it, 

 rarely oblong, 3 — 4-seeded, and a little exceeding the calyx. 

 * Legume l-seeded. Standard of the corolla deciduous. Flowers not yelloio. 



1. T. arvense Linn. : stem erect, simple or branched, pubescent ; leaves 

 on short petioles; leafets obovate-Hnear or cuneate-oblong, somewhat 

 toothed at the apex ; stipules ovate, acuminate ; spikes oblong-cyHndric, 

 very villous; segments of the calyx pilose, equal, setaceous, longer than the 

 corolla. 



Dry pastures. Can. to Flor. May— Sept. (^.—Stem 6—12 inches high. 

 Flowers minute, white or pink. Seeds ovoid, brown. Introduced from Europe. 



Stone Clover. Hare's-foot Trefoil. 



2. T. pratense Linn. : stem suberect, branched; leaves on long petioles-, 

 leafets oval or oblong-ovate, often retuse or emarginate, nearly entire ; stip- 

 ules broad-lanceolate, terminating in a subulate point ; heads of flowers 

 ovate, dense, nearly sessile ; segments of the calyx setaceous, about half as 

 long as the corolla, the lower one longer than the rest. 



Meadows. Can. to Flor. W. to Oregon. May— Oct. %.,—Stem 1—2 feet 

 high. Flowers united into a lube at the base, rose-colored. Seeds yellowish, 

 reniform. Introduced from Europe. Red Clover 



3. T. Pennsylvanicum Willd. : stem ascending, much branched, flexu- 

 ous ; leafets ovate-elliptic, obtuse, very entire ; stipules awned ; heads of 

 flowers ovate-cylindric, solitary, dense ; lower tooth of the calyx shorter 

 than the corolla. 



Woods. Mass. and Penn. June— Sept. %.— Flowers fine red. Resembles 

 T. medium of Linnseus. Introduced ? Buffalo Clover. 



