SPECIES xiND VARIETIES. 219 



M. alba has harder and more wiry stems, narrower leaflets, 

 and white flowers, and is also occasionally found, but probably 

 introduced with corn or ballast. 



(73) Trigonella. Trigonel. 



T. ornithopodioides : annual ; stems thickly matted, spread- 

 ing, rarely more than 2-3 inches long, glabrous ; leaflets in- 

 serted close together at the summit of the stalk, obovate or 

 obcordate, toothed ; flowers small, nearly white, solitary or 

 two or three together in each axil; petals remaining round the 

 pod as in the Clovers ; pod slightly curved, glabrous, contain- 

 ing 6-8 seeds. — Dry sandy pastures, chiefly near the sea. Fl. 

 June, July. 



(74) Trifolium. Clover. 



* Flowers purple or red. 



T. pratense : sterns decumbent or nearly erect, 1-2 feet 

 long, hairy; stipules large, ovate, bristle-pointed; leaflets 

 obovate or obcordate ; flowers reddish-purple, in dense termi- 

 nal ovoid or globular heads, with two sessile, trifoliolate 

 leaves close at their base. — Meadows and pastures. Fl. May 

 to September. 



T. medium : stems ascending zigzag ; stipules linear-lan- 

 ceolate; leaflets elliptical or lanceolate; flower-heads always 

 more or less pedunculate above the last floral leaves; the 

 corolla larger than in the last, brighter and richer coloured. — 

 Open woods and bushy pastures. Fl. June to September. 



T. striatum : annual ; sm.alL tufted, spreading, covered 

 with soft hairs ; stipules ovate, ending in a fine point; leaflets 

 obovate ; flower- heads small, ovoid or globular, chiefly termi- 

 nal, and closely sessile within the last leaves ; calyx softly 



