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Show 322 - DARWINIAN A. never distinctly raised before, no one noticing anything here that needed explanation. Darwinian teleology, however, raises questions like this, and Mr. Darwin not only propounded the riddle but solved it. The object of the partial closing is to permit small insects to escape through the meshes, detaining only those plump enough to be worth the trouble of digesting. For naturally only one insect is caught at a time, and digestion is a slow business with Diomeas, as with anacondas, requiring ordinarily a fortnight. It is not worth while to undertake it with a gnat when larger game may be had. To test this happy conjecture, Mr. Canby was asked, on visiting the Diom£as in their native habitat, to collect early in the season a good series of leaves in the act of digesting naturally-caught insects. Upon opening them it was found that ten out of fourteen were engaged upon relatively large prey, and of the remaining four three had insects as large as ants, and one a rather small fly. "There be land-rats and water-rats" in this carnivorous sundew family. Aldrovanda, of the warmer parts of Europe and of India, is an aquatic plant, with bladdery leaves, which were supposed to be useful in rendering the herbage buoyant in water. But it has recently been found that the bladder is composed of two lobes, like the trap of its relative Dionma, or the valves of a mussel-shell; that these open when the plant is in an active state, are provided with some sensitive bristles within, and when these are touched close with a quick movement. These water-traps are manifestly adapted for catching living creatures; and the few incomplete investigations that have already been INSECTIVOROUS AND CLIMBING PLANTS. 323 made re1~dcr it highly probable that they appropriate their prey for nourishment; whether by digestion or by mere absorpti9n of decomposing animal matter, is 1mcertnin. It is certainly most remarkable that tills family of plants, wherever met with, and under the most diverse conditions and modes of life, should always in some way or other be · predaceous and carnivorous. If it be not only surprising but somewhat confounding to our dassifications that a whole group of plants should subsist partly by digesting animal matter and partly in the normal way of decomposing carbonic acid and producing the basis of animal matter, we have, as Mr. Darwin remarks, a counterpart anomaly in the animal kingdom. While some plants have stomachs, some animals have roots. "The rhizocephalous crustaceans do not feed like other animals by their mouths, for they are destitute of an aliment~ry canal but they live by absorbing through root-like proc:sses the juices of the animals on which they are parasitic." . . . . To a naturalist of our day, Imbued with those Ideas of the solidarity o£ organic Nature which such facts as those we have been considering suggest, the greatest anomaly of all would be that they are really anomalous or unique. Reasonably suppQsing, therefore, that the sundew did not stand alone, Mr. Darwin turned his attention to other groups of plants; and, first, to the bladderworts, which have no near kinship with the sundews, but, like the aquatic representative of that family, are provided with bladdery ~acs, under water. In the common species of Utrioular~a or bladderwort, |