Equisetum.] ~ XCIII. EQUISETACE^E. 553 



barren ones. Sheaths about half an inch long, divided into about 6 

 to 8 lanceolate, scarious lobes, broader than in our other Equisetums. 

 Spike about 6 to 8 lines long, obtuse. Branches, both of the barren 

 and fertile stems, 10 to 16 or more in a whorl, very slender, but not 

 above 2 or 3 inches long, and remarkable for bearing, at the lower 

 nodes at least, whorls of 2, 3, or more smaller branches, which give the 

 plant a very elegant tufted appearance. 



In wet woods, and shady places, in temperate and northern Europe 

 and Asia, from northern Italy and the Caucasus to the Arctic regions, 

 and in North America. Spread all over Britain, but more abundant in 

 Scotland and northern England and Ireland than in the south. Fr. 

 summer, or commencing in spring. 



4. E. pratense, Ehrh. (fig. 1271). Shady E. — Allied to E. sylvaticum 

 in stature and mode of growth ; the fruiting stems at first simple, pro- 

 ducing whorls of branches after the spike is developed ; but the branches 

 of both fruiting and barren stems are always simple, and the spike is 

 larger. The fruiting stems at first resemble those of E. arvense, but 

 are much more slender. The sheaths have seldom less than 1 4, and 

 usually about 20 strise, and long, subulate teeth. E. umbrosum, Willd. 



In moist woods, and shady places, generally distributed over the range 

 of E. sylvaticum, in Europe, Asia, and North America, but probably no- 

 where so common. Has been found in various parts of Scotland, northern 

 and central England, and northern Ireland. Fr. late in spring and summer. 



5. E. limosum, Linn. (fig. 1272). Smooth E.— Stems mostly fruiting, 

 1 to 2 feet high or more, all, including the barren ones, simple, or with 

 few short, simple branches at the middle or upper nodes ; the strise 

 usually about 12 to 20, not prominent. Sheaths about 3 or 4 lines long, 

 with shortly subulate or pointed teeth. Spike about 6 to 8 lines long, 

 obtuse. 



In marshy places, wet ditches, or shallow waters, throughout Europe 

 and temperate Asia, from the Mediterranean to the Arctic regions. 

 Common in Britain. Fr. summer. 



[6. E. littoral e, Kiihlew. (fig. 1273). Bog E. — Intermediate between 

 E. limosum and palustre, with both of which it agrees in habit, but differs 

 from the former in the roughish stem with 10 to 18 distinct deep grooves, 

 and in the upper sheaths having dilated mouths, and from E. palustre in 

 the larger more hollow stems, with 10 to 18 grooves, and in the dilated 

 mouths of the upper sheaths. 



In sandy bogs of Denmark, north and central Germany, and central 

 Russia. In Britain hitherto found only in similar situations at Bisley 

 Common, in Surrey, but is probably overlooked elsewhere, from its 

 similarity to E. palustre.] 



7. E. palustre, Linn. (fig. 1274). Marsh E. — Stems mostly fruiting, 

 but all nearly similar, erect, about 1 to 1J feet high, much thinner than 

 in E. limosum, and marked with only about 6 to 8 prominent striae or 

 angles, and deep furrows ; the branches but few in a whorl, not very long, 

 and not so thin as in some species. Sheaths 3 or 4 lines long, with as 

 many pointed or shortly subulate teeth as stride. Spike as in E. limosum. 



In marshes and spongy bogs, in Europe, temperate Asia, from the 

 Mediterranean to the Arctic regions, and in North America. Common 

 in Britain. Fr. summer. 



8. E. hyemale, Linn. (fig. 1275). Rough E., Butch Rush. — Stems 



