8. _Trifolium procumbens_ is called by the botanist “Hop Trefoil,” from the fact that its dried head of persistent flowers[6] exactly resembles small bunches of hop _strobiles_ (fruiting heads). The foliage is much like that of _Medicago lupulina_, nonsuch, or black medick, which is the “hop” of the farmer; but the whole plant of the true hop trefoil dries up so quickly under the sunshine, and is withal so wanting in succulency and quality, that it cannot be compared with _M. lupulina_ as a fodder plant, and hence it is but little cultivated in the present day. [6] Flowers are so called that remain enveloping the seed while it ripens, which they do in all the clovers. There are other clovers which have been recommended for cultivation, but they are mostly foreign, and do not appear to possess those qualities which should lead us to prefer them before those in common use. There are, too, several additional wild clovers, but they possess no agricultural interest, unless, perhaps, as indicators of soil. The _Trifolium pratense_ (Hare’s-foot Trefoil) is a pretty, wild species, native to light sandy soils, the seed of which is sold for growing “bedding plants.” CHAPTER XIX. ON THE VARIETIES OF RED CLOVERS. The _Trifolium pratense_ of botanical authors is remarkable for the great number of varieties it assumes, even in its wild growth; but these are exceeded in the number of cultivated forms: thus in any rich meadow we may make out several sorts which may be expected to be more or less permanent, whilst the market samples of seed will offer us several varieties for the different countries of America, England, France, Holland, Germany, &c. The following are some of the more prominent of our native wild varieties:— 1. _Trifolium pratense_—Common Red Clover.—Head of pink; flowers, somewhat compact; leaves more or less broad; plant smooth[7] in proportion to its size, the smaller wild specimens being usually very hairy; stem more or less purple. [7] In this, as well as the generality of forms, the smoother and larger growth indicates cultivation, manuring will sometimes make the difference. 2. _Trifolium pratense_, var. _pallidum_—Pale-flowered Clover.—Head of very light pink; flowers large, full, and more rotund than 1, and almost double in size and in the number of its flowers; whole plant more or less hairy; stem green. 3. _Trifolium pratense_, var. _album_—White Clover.—Flowers white; herbage a very light green; in other respects much the same as the last. 4. _Trifolium pratense perenne_—Perennial Red Clover.—Flowers less compact than the common clover, whole plant having stems inclining to dark purple; leaves narrower. 5. _Trifolium pratense perenne_, sub-var. _pallidum_—Pale Perennial Clover.—A larger plant than the parent form, and less hairy.