Upright Yellow Wood-sorrel (_O. stricta_), similar to the last, but with stem more erect; flowers two to eight on one peduncle.
This is not a British plant, though it has become firmly established on many old ruins throughout the country. It is a native of Central and Northern Europe, and according to Loudon was introduced to England in 1573. It is never found growing on rocks in this country, as would be the case were it a native. In some districts it is known as Gillyflower, a name corrupted from the French, _Giroflée de Muraille_. Old writers who use the name Gillyflower refer to the Clove Pink; in the present day the plant usually intended by the term is the Garden Stock. Culpepper calls this Winter Gillyflower. The wild plants are always the single yellow variety.
It is a Cruciferous plant, like the Bittercress and Shepherd’s Purse, and the structure of the flowers is very similar to those. The sepals are very long, and for economy’s sake that part of the petal that is hidden within the calyx is a narrow claw. The long ovary is surmounted by the two-lobed stigma, and develops into a long pod, 2 or 2½ inches long, containing a large number of reddish seeds. It flowers in May and June chiefly, but also irregularly in mild winters.
It is the only species occurring wild, but in the garden it has produced many grand varieties. The name is most probably derived from the Greek, _cheir_, the hand, and _anthos_, flower--that is a flower suited by its fragrance to be held as a bouquet.
The Cruciferæ, to which these plants belong, is an important Natural Order, containing five-and-twenty British genera and a great many species. All are distinguished by the cruciform flowers, by means of which a botanist can distinguish a crucifer at once. Many of our most important garden and kitchen herbs are crucifers, including the majority of our green vegetables and roots, such as cabbage, turnip, radish, mustard (_see_ p. 90), cress, kale, etc.
In marshes and river-meadows in spring this is the most conspicuous plant, and to acquire it the rambler will not hesitate to risk getting wet feet. What time the sallow first puts out her silvery “palm,” the Marigolds then “shine like fire in swamps and hollows grey” (Tennyson). In some districts it is the May-blob, Mare-blob, and Marybud. It has a thick, creeping rootstock, and broadly heart-shaped glossy leaves with very large stipules. After flowering the leaves increase in size considerably, and in some places they reach an enormous size for so small a plant. The flower has no petals, but the five sepals are enlarged and richly coloured, as with gold, and burnished. The centre of the cup is occupied by a number of carpels, which are surrounded by an indefinite crowd of stamens, and which develop after fertilization into as many follicles containing great store of seeds. The plant is poisonous. The flowering time lasts from April till August.