PEA AND BEAN TRIBE 191 



over every part of it. The stem is from four to nine inches long. It is 

 quite a common plant in England, less so in Scotland, and very rare in 

 Ireland. 



10. Boccone's Trefoil {T. hocrdni). — Heads of flowers in pairs, roundish ; 

 calyx cylindrical in fruit, the teeth straight, unequal, awl-shaped ; leaflets 

 inversely egg-shaped, or narrowly lanceolate, toothed, smooth above ; stipules 

 oblong, with a long awl-shaped point. Plant annual. This very rare 

 species was, until recently, believed to be a plant of southern Europe, and 

 not indigenous on our shores ; but it is now known to be truly wild in some 

 dry places in Cornwall, as between the Lizard Point and Kynance Cove. 

 Its stem is from two to four inches in height, and its pink and white flowers 

 appear in July. 



11. Rough Rigid Trefoil {1\ scdbrum). — Flowers in short prickly 

 heads, terminal and axillary ; calyx-teeth unequal, finally spreading ; leaflets 

 with very thick nerves ; stems prostrate. Plant annual. This species often 

 grows with the Soft Knotted Trefoil, on barren, chalky, or sandy fields, near 

 the sea. It is a small spreading plant, producing its inconspicuous whitish 

 flowers in June and July. It is remarkable for its prickly calyxes, espe- 

 cially when in fruit. 



12. Smooth Round-headed Trefoil (T. glomerdtwm). — Heads of 

 flowers terminal and axillary, sessile, roundish ; calyx-teeth broad, very 

 acute, finally turning downwards; leaflets inversely heart-shaped and 

 toothed; stems prostrate. Plant annual. This, which is not a common 

 Trefoil, is very similar in appearance to the last-described species, but its 

 heads of flowers are rounder, and the teeth of its calyxes more spreading 

 and leaf-like. It flowers in June, on gravelly open places, in the east and 

 south of England. 



13. Subterranean Trefoil {T. suUerrdneum). — Flowers 3 — 5 together, 

 in axillary heads, erect, but bent down when in fruit, and sending out 

 branched fibres from their centre, which penetrate into the ground. Plant 

 annual. This is not an uncommon flower during May and June, on dry and 

 gravelly pastures of England, having long slender white blossoms. It is a 

 singular hairy species, a few inches long, its stems branching and lying over 

 the ground. The flower-stalks gradually lengthen, till, at last, the blossom 

 reaches the earth ; the young fruit then bends down, and a number of thick 

 stout fibres rise from the top of the fruit-stalk and bury the seed in the soil 

 while yet attached to the plant. The pods are large and roundish. 



14. Suffocated Trefoil {T. mffocdtum). — Heads of flowers sessile and 

 roundish ; calyx membranaceous, with broadly awl-shaped teeth, bending 

 backwards; petals shorter than the calyx. Plant annual. This rare little 

 Trefoil grows on the coasts of Norfolk and Suffolk, and from Anglesea to 

 Cornwall, in sandy and gravelly pastures. Its stem is about three or four 

 inches high. The heads of flowers are dense and inconspicuous. They are 

 produced in June and July. The whole plant is smooth. 



15. Upright Round-headed Trefoil {T. strktum). — Heads of flowers 

 terminal and axillary, stalked and round ; calyx at length shaped like a bell, 

 with spreading awl-shaped teeth ; leaflets long, narrow, and toothed ; stems 

 erect. Plant annual. The little globular heads of whitish flowers, and the 



