( "3 ) 
GREAT WATER HORSETAIL. 
EQUISETUM TELMATIGEE. 
This is the finest of British Horsetails. It has barren 
and fertile stems. The former sometimes attain the 
height of six or seven feet, and have an erect and 
stately appearance by the banks of rivers and 
streams. They are clothed from the summit to near 
the base with whorls of crowded branches, from thirty 
to forty in a whorl. The stems are thick and smooth, 
and the numerous ribs are very slight. The sheaths 
are close fitting, divided at the margin into slender 
teeth, the same in number as the ribs of the stem, 
and the branches in the whorl. Each branch is from 
eight to ten inches long, and is jointed. 
The colour of the whole is of a pale green. The 
fertile stem is much smaller, and seldom grows more 
than a foot in height; very stout, destitute of 
branches, divided into about fifteen joints, and 
covered with large, loose, pale sheaths with long 
slender teeth. The cones are very large, often 21- 
inches long and i|- in circumference ; the scales are 
very numerous and the capsules attached to them 
arranged in whorls. The presence of silicic acid has 
been observed in this plant by chemists, due to the 
combination of a silicate with an acid known as 
equisetic acid. 
