174 EQUISETACEAL 
common species, growing often in great abundance near standing water, and 
covering places where water has been drained, or growing among the wild 
flowers of the bog, and reminding us of Clare’s lines :— 
‘* Here Horsetail round the water’s edge 
In bushy tufts is spread, 
With rush and cutting leaves of sedge 
That children learn to dread ; 
Its leaves like razors, mingling there, 
Oft make the youngster turn, 
Leaving his rushes in despair, 
A wounded hand to mourn.” 
The creeping underground stem of this species is nearly as large as the 
stem of the frond, black, and smooth, and has tufts of black fibres descending 
from it. The main stem of the frond is perfectly erect, about fifteen inches 
high, with five to twelve prominent ribs and deep furrows, rough to the 
touch, though less so than in some of the species, and whorled throughout, 
except at the base, with numerous branches. The joints are invested with 
nearly cylindrical sheaths, which, being much larger than the stem, loosely 
clasp it, some of the upper ones being nearly twice as large as the stem itself. 
The number of marginal teeth on the sheath is the same as that of the ribs 
on the stem. They are light-coloured, with black or light-brown tips, and 
membranous margins. The fertile and barren stems are alike, their branches — 
greatly varying in length in different circumstances. The cone of fructifica- 
tion is slender, about an inch long, and standing on a footstalk. The whorls 
of scales are, at an early period, crowded into a black mass, but after a while 
are quite separated, showing the white capsules attached to the margin. In 
June, when these catkins are fully ripened, they become of a- brown colour, 
and, after discharging the spores, wither away ; but the bright green whorls 
of rigid branches remain green till late in the autumn. 
There are some singular varieties of this plant, which, however, appear 
to be dependent on soil and situation, and not to become permanent. One 
form has been termed polystachya. Instead of the one cone usually placed, 
in the ordinary form of the Horsetail, on the central stem, several of the 
branches of the two upper whorls terminate in cones, which are usually 
darker coloured than the commoner cone, more compact in form, and appear 
later in the season. 
Another, and rarer variety, called alpina or subnudum, is very much 
smaller than the ordinary plant, scarcely more than three or four inches 
high, having the lower part of the stem prostrate, and the branches only 
about the base of its stem. It is apparently but a dwarfed condition of the 
plant, probably caused by want of nutriment, the result of growth on a soil 
less favourable to luxuriance, or of having been cropped by animals. 
5. Wood Horsetail (£. sylvdticwm).—Stem erect, branches compound, 
bending downwards; sheaths loose; catkin blunt. ‘This pretty species 
differs so much from our other Horsetails, that it is readily distinguished 
even at a glance. Its pale green fronds are by far the most elegant and 
graceful of our native species. In wet sandy places in the north of this 
kingdom the plant is not infrequent, and it must be described rather as local 
than rare in this country. In Germany and Holland it is very common ; it 
