288 CLASS XVII. ORDER IV. 



ViciA sATivA. L. Common Vetch. 



Flowers two, snbsessile ; stipules toothed, marked 

 with a spot ; leafets oblong-ovate, retuse, miicronatcd ; 

 legumes erect, roundish, glabrous. 



Stem slender, quadrangular. Petioles bearing five or six pairs 

 of lanceolatp. truncatid, mucronate leafets. Stipules semisagit- 

 tate, tooilied, with a remarkable scar on the outside. Flowers 

 two or three, axillary, purple. Calyx prismatic with five long 

 teeth. Banner straight, keel very short. Legume rough, com- 

 pressed. About cultivated grounds, probably introduced. — June 

 — Annual. 



ViciA pusiLLA. Willd. Slender Vetch. 



Peduncles solitary, capillary, one flowered. Stipules 

 semisagittate. entire; leafets about six. linear lanceo- 

 late, obtuse; legumes small, oblong, toothed. 



A small and very slender species. Stem square, supported by 

 the tendrils at the ends of the petioles. Leafets small, linear, 

 very obtuse. Flovv'ers very small, whitish, solitary, on slender, 

 axillary peduncles. Legumes oblong, with four or five roundish 

 seeds. — About fences, South Boston. — July. — Annual. 



314. TRIFOLIUM. 



Trifolujm arvense. L. Field Trefoil. 



Heads very hairy, cylindrical; teeth of the calyx 

 bristle shaped, longer than the corolla ; leafets nar- 

 row-obovate. Sm. 



This annual species of trefoil is exceedingly common in roads 

 and dry fields, flourishing in the most barren and gravelly soils. 

 Stem erect, round, hairy, branching. Leaves on short footstalks, 

 consisting of three narrow, inversely ovate, hairy leafets. The 

 flowers grow in long, cylindrical heads, or spikes; the calyx 

 teeth ending in feathery hairs, Avhich project beyond the corolla, 

 give the heads a downy and grayish appearance. Pod very small, 

 one seeded. — July. — August. 



