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Show 292 JJARWINIANA. death of the captive, although it opened very soon when nothing was caught, or when the irritation was caused by a bit of straw, or any such substance. It was Linmeus who originated the contrary and erroneous statement, which has long prevailed in the books, that the trap reopened when the fatigued captive became quiet, and let it go ; as if the plant caught flies in mere play and pastime ! Linnmus also omitted · all allusion to a secreted liquid-which was justifiable, ·as Ellis does not state that he had actually. seen any; and if he did see it, quite mistook its use, supposing ' . it to be, like the nectar of flowers, a lure for msects, a bait for the trap. Whereas, in fact, the lure, if there be any, must be an odor (although nothing is perceptible to the human olfactories); for the liquid secreted by the glands never appears until the trap has closed upon some insect, and held it at least for some hours a pi·isoner. Within twenty-four or fortyeiO'ht hours this glairy liquid is abundant, bathjng a:d macerating the body of the perished insect. Its analogue is not the nectar of flowers, but the saliva or the gastric juice 1 · The observations which compel such an inference are recent, and the substance of them may be briefly stated. The late Rev. Dr. M. A. Curtis (by whose death, two years ago, we lost one of our best botanists and the master in his especial line, mycology), for~y years and more ago resided at WiJ:nj~gton, North Carolina in the midst of the only d1stnct to ' . which the Dionma is native; and he published, m 1834 in the first volume of the " Journal of the Boston Society of Natural History," by far the best ac- INSECTIVOROUS PLANTS. 293 count of this singular plant which had then appeared. He remarks that "the little prisoner is not crushed and suddenly destroyed, as is sometimes supposed," for he had often liberated "captive flies and spiders, which sped away as fast as fear or joy could hasten them." But he neglected to state, although he must have noticed the fact, that the two sides of the trap, at first concave to the contained insect, at length flatten and close down firmly upon the prey, exerting no inconsiderable pressure, and insuring the death of any soft-bodied insect, if it had not already succumbed to the confinement and salivation . . This last Dr. Curtis noticed, and first discerned its import, although he hesitated to pronounce upon its universality. That the captured insects were in some way "made subservient to the nourishment of the plant" had been conjectured from the first. Dr. Curtis "at times [and he might have always at the proper time] found them enveloped in a fluid of mucilaginous consistence, which seems to act as a solvent, the insects being more or less consumed in it." This was verified and the digestive character of the liquid well-nigh demonstrated six or seven years ago by Mr. Canby, of Wilmington, Delaware, who, upon a visit to the sister-town of North Carolina, and afterward at his home, followed up Dr. Curtis's suggestions with some capital observations and experiments. These were published at Philadelphia in the tenth volume of Meehan's Gardeners' Monthly, August, 1868; but they do not appear to have attracted the attention which they merited. The points which Mr. Canby made out are, that |