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Show 290 DARWINIAN A. scale to be manifestly either animal or plant, unless it may be said of some of them that they are each in turn and neither long. There are undoubted animals which produce the essential material of vegetable fabric, or build up a ·part of their structure of it, or elaborate the ·characteristic leaf-green which, under solar light, assimilates inorganic into organic matter, the most distinguishing ftmction of vegetation. On the other hand, there are plants-microscopic, indeed, but unquestionable-which move spontaneously and freely around and among animals that are fixed and rooted. And, to come witl10ut further parley to the matter in hand,. while the majority of animals feed directly upon plants, "for 'tis their nature to," there are plants which turn the tables and feed upon them. Some, being parasitic upon living animals, feed insidiously and furti:vely; these, although really cases in point, are not so extraordinary, and, as they belong to the lower orders, they are not much regarded, except for the . harm they do. ~here are others, an? those of the highest orders, whiCh lure or entrap ammals in ways which may well excite our special wond~ r-all the .more ·so since we are now led to conclude that they not only capture but consume their prey .. As respects the ·two or three most notable mstances the conclusions which have been reached are among' the very recent acquisitions of physiological science. Curiously enough, however, now that they are made out, it appears that they we~e in good part long aO'O attained, recorded, and mamly forgotten. The ea~lier observations and surmises shared the common fate of discoveries made before the time, or by INSECTIVOROUS PLANTS. 291 those who were not sagacious enough to bring out their full meaning or importance. Vegetable morphology, dimly apprehended by Linnreus, initiated by Caspar Frederick W olfi, and again, independently in successive generations, by Goethe and by De Oandolle, offers a parallel instance. The botanists of Goethe's day could not see any sense, advantage, or practical application, to be made of the proposition that the parts of a blossom a.nswer to leaves; and so the study of homologies had long to wait. Until lately it appeared to be of no consequence whatever (except, perhaps, to the insects) whether Drosera and Sarracenia caught flies or not; and even Dionrea excited only unreflecting wonder as a vegetable anomaly. As if there were real anomalies in Nature, and some one plant possessed extraordinary powers denied to all others, and (as was supposed) of no importance to itself! That most expert of fly-catchers, Dionrea, of which so much has been written and so little known until lately, came very near revealing its secret to Solander and Ellis a hundred years ago, and doubtless to John Bartram, our botanical pioneer, its probable discoverer, who sent it to Europe. Ellis, in his published letter to Linnreus, with which the history begins, described the structure and action of the .living trap correctly; noticed that the irritability which called forth the quick movement closing the trap, entirely resided in the few small bristles of its upper face; that this whole surface was studded with glands, which probably secreted a liquid; and that the trap did not open again when an insect was captured, even upon the |