The Dutch Clover or White Clover (_T. repens_) is one of the most familiar of the Trefoils. It is very abundant in English pastures, and has been introduced into Ireland, where it is now often selected as the national emblem in the place of the Wood Sorrel (p. 52), which is regarded by many as the original 'true Shamrock.' The whole plant is smooth or slightly hairy; and its creeping stem, from two to twenty inches in length, sends down root-fibres from its nodes. The leaves have long stalks, with stipules at the base; and the leaflets are broadly oval or obovate, finely toothed, and have usually a lighter, crescent-shaped mark near the middle. The flower-stalks are long, growing from the axils of the leaves; and each one bears a globular head of white or pinkish flowers. The plant flowers from April to the end of the summer. A very similar species--_T. hybridum_--has been introduced into our country, and has now become established in many places where it was formerly cultivated. Its stipules are larger than those of the Dutch Clover; the pod contains only two seeds; and the flowers are usually pinkish. The Common Purple Clover (_T. pratense_) is also largely cultivated for fodder, but it is indigenous, and grows abundantly in most parts as a wild plant. It is very similar to the Dutch Clover in general build, but its stem is more or less erect, the flowers are purple, and the whole plant is generally more hairy. The stipules are ovate, larger, veined, and have long points; and each flower-head has a pair of trifoliate leaves at its base. The individual flowers are about half an inch long; and the hairy calyx has the lower tooth longer than the others. The pod contains only one seed, and is surrounded by the brown, withered corolla, as well as by the calyx, which remains erect while the fruit ripens. This species also flowers from May to the end of the summer. [Illustration: THE PURPLE CLOVER.] Two of the Vetches (_Vicia_--of the order _Leguminosæ_) are also to be included among our spring-flowering field-plants. One of these is the Spring Vetch (_V. lathyroides_), which may be found in flower from April to June on dry pastures. It is a small plant, with a hairy stem that gives off spreading branches, from six to eight inches long, at the base. The leaves are pinnate, with two or three pairs of leaflets, rounded and notched at the apex, and no tendrils. The flowers are small, solitary, of a rich purple colour, situated in the axils of the leaves. The pods are smooth and usually less than an inch long.