168 LEGUMINOS^. Trifolium. 



than the wings, and mostly longer than the keel. Ovary 2 - 6-ovuled : style filiform. 

 Legumes small, membranaceous, 1 - 2- or sometimes 3 - 6-seeded, indehiscent or often 

 dehiscent by the ventral suture, included in the calyx-tube, or sometimes exserted on a short 

 stipe. — Herbs, often caespitose or diffuse. Leaves palmately 3- (rarely 5 - 7-) foliolate, 

 or occasionally pinnately trifoliolate : leaflets usually denticulate ; the veins straight, simple 

 or forked. Stipules growing to the base of the petiole. Flowers in dense spikes or heads ; 

 sometimes only few, and then umbellate, bracteate. 



* Corolla marcescent or dedduonis, never ijellmc : flowers in ovale heads, not deflxoced when old : calyx not inflated after 



flowering. 



1. Trifolium arvense, Linn. Stone Clover. Rahhit-foot. 



Plant somewhat silky-pubescent ; stem erect, branching ; leaflets spatulate-lanccolate, 

 obtuse, longer than the petiole ; stipules ovate, acuminate ; heads oblong-cylindrical, very 

 villous ; teeth of the calyx setaceous, longer than the corolla, at length spreading. — Engl. hot. 

 t. 944 ; Michx.fl. 2. p. 59 ; Ell. sk. 2. p. 202 ; Bigel.fl. Bost. p. 270 ; DC. prodr. 2. p.lQO; 

 Hook. fl. Bor.-Am. 1. p. 131 ; Beck, hot. p. 79 ; Darlingt. Jl. Cest. p. 406 ; Torr. ^ Gr. 

 fl. N.Am. 1. p. 313. 



Annual. Stem 6-12 inches high, usually much branched, but often nearly simple. 

 Leaflets about three-fourths of an inch long, emarginate and mucronate, entire or obscurely 

 serrulate. Stipules with a long subulate point. Spikes from half an inch to an inch long, 

 finally tawny, at first nearly sessile, but at length pedunculate. Corolla very small, white or 

 pale rose-color, with a purple spot on the wings. Legume one-seeded. Seed oval. 



Old sandy fields, sterile hill-sides, etc. ; common. Introduced from Europe. April - No- 

 vember. 



2. Trifolium pratense, Linn. Red Clover. 



Stems ascending ; leaflets oval, obovate or broadly obovate, often retuse or emarginate, 

 nearly entire ; stipules broadly lanceolate, acuminate with a long subulate point ; heads of 

 flowers ovoid, dense, nearly sessile, bracteate ; teeth of the calyx setaceous, lower one much 

 longer than the others, which are equal and about half the length of the corolla. — Pursh, fl. 

 2. p. 478 ; Engl. hot. t. 1170 ; Ell. sk. 2. p. 202 ; DC. prodr. 2. p. 195 ; Bigel. Jl. Bost. 

 p. 271 ; Hook. fl. Bor.-Am. 1. p. 191 ; Beck, hot. p. 79 ; Darlingt. fl. Cest. p. 406 ; Torr. 

 4- Gr.fl. N.Am. 1. p. 314. 



Root perennial, according to most authors ; biennial, according to some. Stem from 1 to 

 2 feet high or more. Leaflets often marked with a whitish lunulate spot. Flowers purplish 

 red ; the petals united into a tube at the base. Legume one-seeded. Seed nearly reniform. 



Meadows, cultivated fields, etc. ; extensively naturalized. May - September. — The 

 Common Red Clover is well known as a most valuable fodder plant ; making either by itself, 

 or mixed with true grasses, the best sort of hay. "Authors generally consider this species a 



