very narrow, coloured bag. and they are clothed externally with a pile of
short, dichotomous, moniliform coloured filaments, which form the coat of
the frond. Fructification; spherical masses of closely compacted, mmute
spores abundantly scattered among the filaments of the periphery. Ootour
a fine, clear, rosy-crimson. Substance tender, sUppery and gelatinous, very
closely adhering to paper in drying.
A liiglily beautiful plant, nearly related in affinity to tbe genus
Dudresnaia, but, according to tbe views of tbe late Captain
Carmicbael of Appin, forming tbe type of a separate genus, wbicb
differs from Dudresnaia cbiefly in having a tubular axis. Tbe
structure, as seen by tbe microscope, is very beautiful, and sucb
tbat it is impossible to do it justice in drawing, the extreme
lubricity and transparency of the parts being lost in a lithograph.
The whole plant is very tender, and invested with a gelatinous
pellicle, and each filament of which it is composed stands separated
from its neiglibour by a similar coating. These characters
are lost in our plate, wliich is, in other respects, a faithful portrait.
Gloiosiphonia capillaris is one of those species which is rather
uncertain in its appearance, being found in some seasons in considerable
plenty, and not occurring again, sometimes, for several
years. The causes of sucb temporary disappearances of certain
sea plants are very obscure, and will probably long remain so.
The most probable seem to be changes wbicb may take place in
tbe bottom of the sea by tbe shifting of sand or gravel, an overflowing
of wbicb would smother tbe vegetation, and would not
afford sufficient stability for the roots of a new crop. In many
instances this cause no doubt prevails. In some others, tbe
difference of temperature, small as this is, of different seasons,
appears to be the chief, or tbe only, cause of failure.
Fig. 1. G l o io s i p h o n ia o a p i l l a b i s -.— natural size. 2. A small branchlet.
3. Transverse section of the tubular frond. 4. A segment of the same,
enlarged. 5. A longitudinal section of the frond ;— all more or less lagUij
magnified.