HORSE-TAIL. 33 



Description. — The root is perennial, slender, dark-brown, 

 creeping", and jointed, with numerous capillary fibres. The sterile 

 stems are decumbent at the base, rising from one to two feet 

 in height, with undivided, ascending", whorled branches, angular, 

 with about twelve striee, microscopically tuberculate, leafless, but 

 furnished at each articulation with about twelve subulate, erect, 

 dark-brown sheaths, which are membranous at the margin ; the 

 fertile stems, which appear before the sterile ones, are from six to 

 eight inches high, erect, unbranched, leafless, smooth, tubular 

 within, and of a silvery-brown colour externally ; the sheaths are 

 distant, erect, long, cylindrical, ventricose, striated, incised, and 

 toothed. The fructification terminates the stem in a long, oblong, 

 lanceolate spike, of a light-brown colour. (See Gen. Char.) 

 Plate 28, fig. 2, («) one of the peltate scales magnified, with its 

 involucres discharging the capsules or sporules ; (6) capsule, mag- 

 nified. 



This singular plant, which has been fancifully compared to a 

 miniature pine-tree, is common in corn-fields and by road-sides in 

 most parts of Britain. The fructification appears in March and 

 April, after which the stems wither and disappear, and are suc- 

 ceeded by the sterile stems, which continue throughout the summer. 

 The generic name is formed from equus, a horse, and seta, a 

 hair or bristle, signifying Horse-tail, in allusion to the form 

 of the stem. The nnrspi$ of Dioscorides, and the Equisetum, 

 Ephedron, and Anabasis of Pliny, are supposed to refer to one or 

 other of these plants. 



Eight British species of this genus are described. Excepting 

 the one now before us, the great Water Horse-tail (E.fluviatile) 

 is, perhaps, the most common : its branches are very numerous, 

 often thirty in a whorl, and it forms a conspicuous object by the 

 sides of rivers, lakes, and pools, in spring, its stems being fre- 

 quently four or five feet high. The branched Wood Horse-tail 

 (E. sylvaticum) is a graceful plant, inhabiting moist woods and 

 hedge-banks ; it is distinguished by its compound, whorled, deflexed 

 branches, and sheaths with membranous obtuse teeth. The rough 

 Horse-tail (E. hyemale) goes by the names of Shave-grass and 

 Dutch rushes. In a botanical point of view, these plants constitute 

 an anomalous family, the nature and relative functions of their 

 reproductive organs being by no means well understood. 



Qualities and General Uses. — The cuticle of the stems of 



VOL. II. d 



