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BRITISH FLOWERING PLANTS

black spots, and thick yellow bodies, with rows of longitudinal black spots.

Order X.Droseracecæ (I genus)

This is another small Order, represented in Britain by only one genus. Three species are not uncommon in swampy places. They are low- growing plants ; the flowers have 5 sepals, petals and stamens, and the leaves are set with long hairs which exude a viscid substance. When an insect settles on the leaf, the leaf bends over and captures it, and does not again unfold till the juices of the prey have been absorbed. But the plant does not catch more insects than it requires, ceasing to do so when it has obtained sufficient for its needs. An American species, Venus's Fly-trap {Dioncea muscipula), often to be seen in botanic gardens, is particularly celebrated for its fly-catching propensities ; but our British Sundews have the same habit, though their leaves do not close so completely in the rat-trap fashion of Dioncea, which has the edges of the leaves set round with long spine-like hairs.

In the Common Sundew (Drosera rotundifolia) the leaves are nearly circular, the stem is erect, and the capsule is not furrowed. The Oblong Sundew (D. longifolia) has erect stems, a furrowed capsule, and erect leaves, much longer than broad. The English Sundew (D. anglica) which, notwithstanding its name, is less common in England than in other parts of the British Islands, has erect leaves, much longer and narrower than in the other species.

The flowers are white, at the end of a stalk from 2 to 8 inches high, and expand in the sunshine. Hybrids between the different species are not uncommon.

A preparation of Drosera rotundifolia has been employed as a sedative in asthma and whooping cough.

Order XI. Frankeniacecæ (1 genus)

The only British representative of this Order, the Sea Heath {Frankenia lavis) is a low decumbent spreading plant with shoots 6 inches long or more, with small opposite leaves, small pink flowers,