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attributed to drought; and seems to be one of those occasional
and inconstant variations to which plants are liable,
as they are influenced by the external circumstances of soil
or climate, or the peculiarities of the seasons.
The barren stems of this species are very stately objects
when in a luxuriant condition of growth. They grow erect,
and are from six to seven feet or more in height, clothed
nearly to the bottom with spreading proximate whorls, those
on the stouter parts consisting of thirty to forty branches,
which are sometimes again branched. The upper whorls
have many fewer branches. The whorls are most crowded
towards the top of the stem, and there also the branches
are about the full length—six or eight inches; lower down
the stem the branches become shorter, and the whorls more
distant. The stems measure about an inch and a half in
diameter at the stoutest part, and from this point decrease
upw'ards, becoming very slender at the point. The surface
is smooth, with mere indications of about thirty faint lines
extending into the sheaths, and there becoming more apparent.
The sheaths set close to the stem, or nearly so, and
are half an inch long, green below, with a dark brown ring
at top, and divided at the margin into slender bristly teeth,
about half an inch long, dark brown, with paler membranous
edges; the teeth frequently adhere together at the summit
in twos and threes. The branches have eight or ten ribs
united in pairs, and their sheaths terminate in four or five
teeth, each extended into a slender black bristle, and having
two denticulated ribs. The branches very frequently produce
a series of two to five secondary branches at their
second joints. The colour of the main stem is very pale,
scarcely tinged with green, that of the branches a delicate
green. The sheaths of the branches, in this and some other
species, furnish excellent marks for discrimination.
The fertile stem is erect, simple, from nine inches to a foot
or more high, succulent, pale brown, and smooth. Erom
each of the numerous joints arises a large loose funnel-
shaped sheath, the upper ones being largest; they are distinctly
striated, and terminate in thirty to forty long, slender,
and, according to Hooker, two-ribbed, teeth. The
sheaths are pale greenish-brown below, darker brown above.
The catkins are large, between two and three inches lon g ;
the scales, often numbering four hundred, are arranged in
whorls, of which the lower ones are usually very distinct.
The scales and spore-cases resemble those of the allied kinds.
A section of the barren stem of this species shows an outer
surface without ridges and furrows, and in the very narrow