LYCOPODIUM, the principal genus of the Lycopodiaceae, a natural order of the Fern-allies (see Pteridophyta). They are flowerless herbs, with an erect, prostrate or creeping widely-branched stem, with small simple leaves which thickly cover the stem and branches. The “fertile” leaves are arranged in cones, and bear spore-cases (sporangia) in their axils, containing spores of one kind only. The prothallium developed from the spore is a subterranean mass of tissue of considerable size, and bears the male and female organs (antheridia and archegonia). There are about a hundred species widely distributed in temperate and tropical climates; five occur in Britain on heaths and moors, chiefly in mountainous districts, and are known as club-mosses The commonest species, L. clavatum, is also known as stag-horn moss.
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| From Strasburger’s Lehrbuch der Botanik, by permission of Gustav Fischer. | |
| Fig. 1.—Lycopodium clavatum. | |
| A, Old prothallus. B, Prothallus bearing a young sporophyte. G, Polian of a mature plant, showing the creeping habit, the adventitious roots and |
the specialized erect branches bearing the strobile or cones. H, Sporophyte bearing the single sporangium on its upper surface. J, Spore. |
Gerard, in 1597, described two kinds of lycopodium (Herball, p. 1373) under the names Muscus denticulatus and Muscus clavatus (L. clavatum) as “Club Mosse or Woolfes Clawe Mosse,” the names being in Low Dutch, “Wolfs Clauwen,” from the resemblance of the club-like or claw-shaped shoots to the toes of a wolf, “whereupon we first named it Lycopodion.” Gerard also speaks of its emetic and many other supposed virtues. L. Selago and L. catharticum (a native of the Andes) have been said to be, at least when fresh, cathartic; but, with the exception of the spores of L. clavatum (“lycopodium powder”), lycopodium as a drug has fallen into disuse. The powder is used for rolling pills in, as a dusting powder for infants’ sores, &c. A tinctura lycopodii, containing one part of the powder to ten of alcohol (90%), has been given, in doses of 15 to 60 minims, in cases of irritation and spasm of the bladder. The powder is highly inflammable, and is used in pyrotechny and for artificial lightning on the stage. If the hand be covered with the powder it cannot be wetted on being plunged into water. Another use of lycopodium is for dyeing; woollen cloth boiled with species of lycopodium, as L. clavatum, becomes blue when dipped in a bath of Brazil wood.