LOBE'LIA, a genus of exogenous plants of the natural order lobellacece. This order is nearly allied to campanulacew, one of the most conspicuous differences being the irregu lar corolla. It contains almost 400 known species, natives of tropical and temperate climates, abounding chiefly in damp woods in America. and the n. of India. They are generally herbaceous or half-shrubby, and have a milky juice, which is often very acrid, and often contains much caoutchouc. A poisonous character belongs to the order, and some arc excessively acrid, as tupa fuillci, a Chilian and Peruvian plant, of which the very smell excites vomiting; yet the succulent fruit of one species, centropogon surina mensis, is eatable.—The genus Lobelia is the only one of this order of which any species are British. The-WATER LOBELIA (L.dortmanna) is frequent in lakes with gravelly bottom, often forming a green carpet underneath the water with its densely matted, sub-cylin drical leaves. The flowers are blue, the flowering stems risin,,o. above the water.—To this genus belong many favorite g-,arden flowers, as the beautiful CARDINAL FLOWERS 4L. cardinalls, L. fulgcns, and L. splendens) and the BLUE CARDINAL (L. syphilitica), natives of the warmer parts of North America. perennials, which it is usual to protect 41tiring winter in Brita,in. To this genus belongs also the INDIA:sr TOBACCO of North
America (L. inflata), an annual, with an erect stem, a foot high or mere, with blue flow ers, which has been used as a medicine from time immemorial by the aborigines of North America, and was introduced into this country in 1829 by Dr. Reece. Both the flower inm-herb aud the seeds are imported. It is the former, compressed in oblong cakes, . wiiich is chiefly employed. The chemical constituents of Lobelia are not accurately known. A liquid alkaloid, lobelina, and a peculiar acid, to which the term lobelic acid been applied, have been obtained from it.
In small doses, it acts as diaphoretic and expectorant; in full doses (as a scruple of the powdered herb), it acts as a powerful nauseating emetic; while in excessive doses, or in full doses, too often repeated, it is a powerful acro-narcotic poison. It is the favorite remedy of a special class of empirics, and consequently deaths from its admin istration are by no means rare. Physicians seldom prescribe it now, except in cases of Asthma.
In a case of poisoning by this drug, the contents of the stomach should be withdrawn as speedily as possible. If the stomach pump is not at hand, an emetic of sulphate of :zinc or of mustard should be administeiied.