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Show 300 DAR WINIA-?f A. der instead of the summit only. Very curious, and ·even somewhat painful, is the sight when a fly, alighting upon the central dew-tipped bristles, is held as fast as by a spider's web; while the efforts to escape not only entangle ~he insect more hopelessly as they exhaust its strength, but call into action the surrounding bristles, which, one by one, add to the number of the bonds, each by itself apparently feeble, but in their combination so effectual that the fly may be likened to the sleeping Gulliver made fast in the tiny but multitudinous toils of the Liliputians. Anybody who can be~ieve that such an apparatus was not intended to capture flies might say the same of a spider's web. Is the intention here to be thought any the less real because there are other species of Drosera which are not so perfectly adapted for fly-catching, owing to the form of their leaves and the partial or total want of cooperation of their scattered bristles~ One such species, 'D. filiformis, the thread-leaved sundew, is not uncommon in . this country, both north and south of the district that Dionrea locally inhabits. Its leaves are long ~md thread-shaped, beset throughout with glutinous gland-tipped bristles, but wholly destitute of a blade. Flies, even large ones, and even moths and butterflies, as Mrs. Treat and Mr. Canby affirm · (in the American Naturalist), get stuck fast to these bristles, whence they seldom escape. Accidental as such captures are, even these thread-shaped leaves respond more or less to the contact, somewhat in the manner of their brethren. In Mr. Canby's recent and simple experiments, made at .Mr. Darwin's suggestion, INSECTIVOROUS PLANTS. 301 when a small fly alights upon a leaf a little below its slender a~e~, or when a bit of crushed fly is there affixed, Withm a few hours the tip of the leaf bends at the point of contact, and curls over or around the ~ody in question ; and Mrs. Treat even found that when living flies were pinned at half an inch in distance from the leaves, these in forty minutes had bent their tips perceptibly toward the flies, and in less than two hours reached them I If this be confirmed-and such a statement needs ample confirmation-then it may be suspected that these slender leaves not only incurve after prolonged contact, just as do the leaf-stalks o~ many climber~, but also make free and independent circular sweeps, In ·the manner of twining stems and of many tendrils. Correlated movements like these indicate purpose. When performed by climbing plants, the object and the advantage are obvious. That the apparatus and the actions of Dionooa and Drosera are purposeless and without ~dvan~age to the plants themselves, may have been believed In former days, when it was likewise conceived that abortive and functionless organs were s~ecially created "for the sake of symmetry" and to display a plan ; but this is not according to the genius of modern science. In the cases of insecticide next to be considered such evidence of intent is wanting, but other and cir-' cumstantial evidence may be had, sufficient to warrant conviction. Sarracenias have hollow ,leaves in the form of pitchers or trumpet-shaped tubes, containinowater, in which flies and other insects are habituall; drowned. They are all natives of the eastern side of |