Page:An introduction to physiological and systematical botany (1st edition).djvu/105

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VARIETIES OF SECRETIONS.
75

It is curious to observe, not only the various secretions of different plants, or families of plants, by which they differ from each other in taste, smell, qualities and medical virtues, but also their great number, and striking difference, frequently in the same plant. Of this the Peach-tree offers a familiar example. The gum of this tree is mild and mucilaginous. The bark, leaves and flowers abound with a bitter secretion of a purgative and rather dangerous quality, than which nothing can be more distinct from the gum. The fruit is replete, not only with acid, mucilage and sugar, but with its own peculiar aromatic and highly volatile secretion, elaborated within itself, on which its fine flavour depends. How far are we still from understanding the whole anatomy of the vegetable body, which can create and keep separate such distinct and discordant substances!

Nothing is more astonishing than the secretion of flinty earth by plants, which though never suspected till within a few years, appears to me well ascertained. A substance is found in the hollow stem of the Bamboo, (Arundo Bambos of Linnæus, Nastos of Theophrastus),