240 HISTORY OR BRITISH REENS.
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regards this one point. Their resemblance consists-in both
growdng up at the same time, and both putting out whorls
of deflexed branches, less numerous certainly on the fertile
stems ; but in other respects they differ, as, for instance,
in the growth of the apices of the fronds. The fertile ones,
terminating in a catkin which soon perishes, become hlunt-
topped, while the barren ones continue to elongate at the
point and so become somewhat pyramidal. The barren
stems are also more slender than the fertile ones, and have
less inflated sheaths. It will thus appear, that this species,
in its habit of growth, holds a middle rank between that
group in which the fertile and barren stems are successive
and quite dissimilar, and that group in which they are
simultaneous and present no appreciable difference of structure.
Something of the same kind occurs in E. umbrosum,
as will be found noticed under that species.
The fertile stems, when they first shoot up, are almost quite
simple, and a few of them remain so, perfecting their conelike
head, and then perishing. More usually, by the time
the catkin has become fully grown, the whorls of branches
from the upper joints will be seen protruded to the length of
from half an inch to an inch or rather more. Two, three,
or four, rarely more, whorls of branches are thus produced
from the uppermost joints of the stem, and above these the
ohlong-ovate blunt cone is seated on a bare stalk-like portion
of the stem, one to two inches long. The stems are round,
succulent, pale-coloured, with about twelve slender ridges,
and corresponding shallow furrovrs, nearly smooth, the
siliceous particles which coat the surface being too minute
to impart much roughness. The sheaths are large and loose,
and are divided at the margin into three or four bluntish
lobes; their lower half or tubular portion is pale green,
their upper half or lobes bright russet; they have an equal
number of ribs, with the ribs on the stem. The slender
branches, which are deflexed, grow to about a couple of
inches in length, and produce from their joints a series of
secondary branches, which grow from about half an inch to
an inch in length. The average height of the fertile stems
is about one foot.
The barren stems are more slender and less succulent
than the others; they also produce more numerous whorls
of branches. These grow from fifteen to eighteen inches
high, and are ribbed like the others, only somewhat more
prominently. The sheaths fit closer than those of the
fertile stems, but in colour and in the division of their
margin they resemble them exactly. The whorls of branches
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