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Show 306 DARWINIAN A. the earliest native botanist of this country. Fine writing was his foible; and the preface to his wellknown " Travels" (published at Philadelphia in 1791) is its full-blown illustration, sometimes perhaps deserving the epithet.which he applies to the palms of Florida-that of pomposity. In· this preface he declares that" all the Sarracenias are insect-catchers, and so is the Drosera rotundifolia. Whether the insects caught in their leaves, and which dissolve and mix with the fluid, serve for aliment or support to these kind of plants is doubtful," he thinks, but he should be credited with the suggestion. In one sentence he speaks of the quantities of insects which, "being invited down to sip the mellifluous exuvia from the interior surface of the tube, where they inevitably perish," being prevented from returning by the stiff hairs all pointing downward. . This, if it refers to the sweet secretion, would place it below, and not, as it is, above the bristly surface, while the liquid below, charged · with decomposing insects, is declared in an earlier sentence to be "cool and animating, limpid as the morning dew." Bartram was evidently writing from · memory; and it is very doubtful if he ever distinctly recognized the sweet . exudation which entices insects. Why should these plants take to organic food more than others ~ I£ we cannot answer the question, we may make a probable step toward it. For plants that are not parasitic, these, especially the sundews, have much less than the ordinary amount of chlorophyllthat is, of the universal leaf-green upon which the formation of organic matter out of inorganic materials INSECTIVOROUS PLANTS. 307 depends. These take it instead of making it, to a certain extent. What is the bearing of these remarkable adaptations and operations upon doctrines of evolution~ There seems here to be a field on which the specific creationist, the evolutionist with design, and the necessary evolutionist, may fight out an interesting, if not decisive, " triangular duel." |