TREFOIL, or Trifolium, L. a genus of fifty-five species, 16 of which are indigenous: of these we shall mention the following:

1. The pratense, or Common Clover;

2. The medium, v. alpestre, or Red, Perennial Clover;

3. The procumbens, v. agrarium, Hop-clover, or Hop-trefoil; and

4. The repens, or White Clover. See vol. ii. pp. 9—12.

5. The Melilotus officinalis, or Melilot-trefoil. See Melilot the Common.

6. The arvense, or Hare's-foot Trefoil, grows in sandy pastures, corn-fields, and chalky situations; where it flowers in July and August. This species is strongly aromatic; and, when dried, retains its odour for a considerable time:—it affords a grateful food to cattle; and is, by Bechstein, recommended as a valuable substitute for oak-bark, in tanning leather.

7. The fragiferum, or Strawberry Trefoil, thrives in moist meadows, chiefly in the vicinity of London, where it flowers in August.—This perennial vegetable is industriously cultivated by the Greenlanders, who propagate it by seed, and also transplant the stalks, which thus attain the height of seven feet. Its whitish and reddish flower-heads are nearly globular, and slightly compressed on the upper surface. The whole plant affords as nutritive food to cattle as the Common or Meadow-clover.