and throw out at the dissepiments a second set of lesser ranmU. In aU
the main stem is soUd, aud densely cellular ; the ramuli hollow, fiUed with
a watery fluid. Ceramidia spherical, with a wide pellncid border, sessile on
the sides of the ramuli. Tetraspores tripartite, scattered through the surface
ceUs of the ramuli, on distinct plants. Substance cartüaginons in the
stem ; membranaceous and soft in the ramuli. Colour, when in vigour, a
deep brownish full-red, afterwards becoming pale, then pink, and finally
whitish or greenish in old age. The colour is given out by steeping in
fresh water, and the plant adheres closely to paper, when diled with pressure.
There is some difference in habit betwen this plant and the
other members of the genus Chylocladia, but so close an affinity
in the more important points of its structure, that it appears
very undesirable to separate it from them, as has been proposed
by Prof. Kiitzing. Except in having a solid, cellular stem and
branches, the hollow and jointed portions being confined to the
ramuli, there is nothing to separate it from C. haliformis, the
type of the genus. Indeed, as Dr. Greville well remarks, the
relationship between C. ovalis and C. haliformis is very close,
especially in that variety of the former, in which the ramuli are
lengthened, and bear several joints, somethnes furnished with
the commencement of new whorls. Both are remarkable for
the wide, pellucid epidermis, which covers the whole plant, and
for a peculiar modification of the ceramidium, which in these
species resembles, in form, the fruit called coccidium, though
the arrangement and shape of the spores are essentially the
same as in more usual states of the organ.
Chylocladia ovalis, is in greater perfection in the months of
April and May, at which season, on the west coast of Ireland, it
forms a conspicuous feature in the marine fiora, its densely tufted
succulent fronds being then of a dark red colour, and produced
in the greatest abundance. Two months later, its aspect is completely
changed ; great multitudes of the fronds have perished,
and those that remain are faded in colour, with attenuated and
more compound ramuli. By the end of August the plant has
almost entirely disappeared.
Kg. I . Chylooladia ovalis :— o f the natural size. 2. A ramulus with tetra-
spores. 3. Portion of the surface, m th tetraspores imbedded. 4. Pa-
muius Avith ceramidia. 5. Longitudinal section of the stem. 6. Transverse
semi-section of the same. 7. Longitudinal section of a ramulus, showing
the diaphragms :— all ;