270 Class XVII. Order IV. 



VICIA SATIVA. L. Common Vetch. 



Flowers two, subsessile ; stipules toothed, marked 

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

 legumes erect, roundish, glabrous. 



Stem slender, quadrangular. Petioles bearing five or six 

 pairs of lanceelote, truncated, mucronate leafets. Stipules 

 semisagittate, toothed, with a remarkable scar an the outside. 

 Flowers two or three, axillary, purple. Calyx prismatic with 

 five long teeth. Banner straight, keel very short. Legume 

 rough, compressed. About cultivated grounds, probably intro- 

 duced. 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. Flowers very small, whitish, solitary, on slender, 

 axillary peduncles. Legumes oblong, with four or five roundish 

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



291. TRIFOLIUM. 

 TRIFOLIUM ARVENSE. L. Field Trefoil. 



Heads very hairy, cylindrical ; teeth of the calyx 

 bristle shaped, longer than the corolla ; leafets narrow- 

 obovate. Sm. 



This annual species of trefoil is exceedingly common in 

 roads and dry fields, flourishing in the most barren and gravelty 

 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, which project 

 beyond the corolla, give the heads a downy and grayish appear- 

 ance. Pod very small, one seeded. July. August. 



