These and the few other spring flowers of heaths and moors are described, in their order, among the summer flowers of the present chapter. Some of them are exclusively spring blossoms, and are to be seen only in their fruiting stages during the summer months, but a few continue to bloom after spring has ended, and even far into the summer. The Furze, which often commences to flower during the first few weeks of the year, may be seen, still in bloom, during July and early August; and the Eyebright may be found in flower even to the beginning of autumn. The Musk Thistle, too, though its first flower-heads may be observed in May, or, sometimes, even in April, will continue producing new flowers well into October. [Illustration: THE MILKWORT.] A good many species are included in the present chapter, and most of these, at least, will be easily identified by the descriptions given. On almost all heaths and downs we may see the pretty little Milkwort (_Polygala vulgaris_)--the only British representative of its order (_Polygalaceæ_), unless we regard some varieties of this variable plant as distinct species, according to the opinions of some authorities. It is a smooth or slightly hairy plant, with a woody stem that gives off several spreading branches varying from two to nine inches in length. The nature of the leaves and the arrangement of the flowers are shown in our illustration. The latter are very variable in colour, ranging from a pure white to lilac and a deep, rich blue; and each has five sepals, of which the two inner ones are wing-shaped, persistent, and coloured like the corolla; and at its base are three bracts, the middle and largest of which is as long as the short pedicel. The petals, three to five in number, are united, smaller than the wing-sepals, and the lowest is keel-shaped. The plant blooms from June to August; and the drooping flowers, though small, are often so abundant as to distinctly modify the general colouring of patches of heath and moor. [Illustration: THE BROOM.] Two small species of St. John's Wort (order _Hypericaceæ_) are moderately abundant on downs and commons, especially in South Britain. The flowers of this order are all yellow, and may be easily recognised by their stamens, three or five in number, which are so much branched that they give the appearance of a large number of stamens arranged in three or five clusters. In the two species we have to consider these stamens are three in number. One is the Trailing St. John's Wort (_Hypericum humifusum_), a little tufted, prostrate plant, with small oblong leaves marked by minute transparent spots, and by black dots under the margins; and flowers with unequal sepals. The other is the Small St. John's Wort (_H. pulchrum_) which is erect, from one to two feet high, with cordate leaves that embrace the stem, and panicled flowers which are tipped with red when in the bud. Both species flower during July and August.