pcUucid, those of the main branches four or five times longer than broad ;
of the upper branches gi'adually shorter ; of the ramuli exceedingly short ;
all deeply coloured at the swollen joints. Tetraspores immersed in the
joint, several in each, disposed in a whorl. Favellæ surrounded by an
involucre of several (4-5) short incurved ramuli, either sessile in the upper
forks or borne on lateral peduncles. Substance soft, but rather firm ; glossy
when diy, and adhering pretty firmly to paper. Colour, a brownish-red,
with a purplish tinge ; sometimes more clearly purple.
Our figure is intended to represent the typical form of the old
Conferva diaphana of British authors, the longest knovvn of the
extensive group of the genus to which it belongs ; a group
which contains numerous very distinct plants, which were once
confounded together as varieties of the species now under review.
From the British species of this section, except one, our C. diaphanum
may be at once knoum by its larger size and more robust
filaments; it is also well characterized by the lateral dichotomous
ramuli given off all along the principal divisions of the frond,
and by the gradually attenuated filaments. These last characters
distinguish it from C. nodosum and C. fastiyiatum.
Limited as it now is, the species has a very wide range, being
found in most of the temperate parts of the sea. Though existing
on all our coasts, from north to south, it does not appear to be
very abundant anywhere, seldom growing in society: the tufts
being thinly scattered here and there through the rock-pools.
When growing, few Algse are more delicately beautiful; and even
in a dry state it forms a very handsome object, the brilliancy and
regularity of the dot-like joints, connected by hyaline, glistering
spaces, having the effect of a piece of fine tracery.
Fig. 1. Ceeamium d ia ph a n um :— o f the natural size. 2. Brancli, with tetraspores.
3. Joints from tlie same. 4. A tetraspore. 5. Branch witb
faveUæ. 6. .Joints from the same, witb involucrated favellæ :— all more or