This species has three kinds of stems. The first of these is about six inches in height, and is provided with large loose sheaths. This bears the cone of fructification, which is ripened about the month of April. The second type of stem produces both branches and a fertile cone, though this latter is very much smaller than in the case of the first type of stem. Finally, there is the barren stem, which may be about eighteen inches in height; this is very rough, and has about twenty strongly-marked ridges. The sheaths, which are not so large as those of the fertile stem, fit somewhat closely. The stem branches freely, and it is to be noted that these branches have three or four ridges; as well, they bear sheaths which end in the same number of teeth. A distinctive feature of the Shade Horsetail is that the topmost whorls of branches spread upwards in such a way that they reach the summit of the stem; there is no long tapering point such as is to be seen in the case of the Field Horsetail, for instance. The result of this habit of growth is that the plant has a curious flat-topped appearance; it is on this account that the species has received one of its popular names. The Shade Horsetail grows in damp meadows and very shady woods, though it is not common in all districts. _Equisetum sylvaticum._ In this case the specific name is taken from the Latin _silva_, “a wood,” and is a reference to the habitat of the plant. The Wood Horsetail. This is one of the most beautiful of our Horsetails. The plant has two kinds of stems, both of which are ultimately branched. The fertile stems put in an appearance first of all in the early spring; at this time these bear only a cone and are without branches. With the dispersal of the spores the cone shrivels up, and then the stems starts to send out green branches. These branches give off whorls of smaller branches from their joints. In a general way the stems of the barren shoots are not so succulent as those which bear the cone; the barren stems, too, are somewhat taller and branch more freely than the fertile ones. In both barren and fertile stems are to be noticed the whorls of small drooping branches which give a characteristic appearance to the Wood Horsetail, and by means of which it may always be identified. The sheaths which enclose the stem evidence three or four teeth, whilst the terminal branches (which are three-ribbed) bear at each joint a sheath ending in three long pointed teeth. The stems of the Wood Horsetail are marked by about a dozen ridges. The Wood Horsetail is often abundant in damp shady woods. _Equisetum palustre._ The specific name _palustre_ means “belonging to the marshes.” The Marsh Horsetail.