Scientific American Supplement, No. 829, November 21, 1891 by Various
page 31 of 146 (21%)
page 31 of 146 (21%)
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or much reduced. There are five petals inserted on the ovary, and
external to a fleshy disk. Each petal has its tip inflexed, giving it an obcordate appearance. The common colors of the corolla are white, yellow, or some shade of blue. Alternating with the petals, and inserted with them, are the five stamens. The fruit, upon which so much stress is laid in the study of the family, is compound, of two similar parts or carpels, each of which contains a seed. In ripening the parts separate, and hang divergent from a hair-like prolongation of the receptacle known as the gynophore. Each half fruit (mericarp) is tipped by a persistent style, and marked by vertical ribs, between or under which lie, in many genera, the oil tubes or vittæ. These are channels containing aromatic and volatile oil. In examination the botanist makes delicate cross sections of these fruits under a dissecting microscope, and by the shape of the fruit and seed within, and by the number and position of the ribs and oil tubes, is able to locate the genus. It, of course, requires skill and experience to do this, but any commonly intelligent class can learn the process. It goes without saying, and as a corollary to what has already been stated, that these plants should always be collected in full fruit; the flowers are comparatively unimportant. Any botanist would be justified in declining to name one of the family not in fruit. An attempt would often be mere guesswork. In this family is found the poison hemlock (Conium) used by the ancient Greeks for the elimination of politicians. It is a powerful poison. The whole plant has a curious mousy odor. It is of European origin. Our water hemlock is equally poisonous, and much more common. It is the _Cicuta maculata_ of the swamps--a tall, coarse plant which has given rise to many sad accidents. _Æthusa cynapium_, another |
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