red-brown in drying. Substance when young, extremely soft and flaccid, 
most closely adhering to paper ; when old, rigid, and coarse, with squarrose 
ramelh. 
One of the handsomest of the British species of this extensive 
genus, especially when young, at which period the whole plant is 
of the softest substance and most delicate rosy-red colour. In 
some respects this species connects the genera Polysiphonia and 
Dasya, for here, although the tetrasporic fruit is altogether that 
of a true Polysiphonia, the habit of the frond is that of Dasya; 
the byssoid ramelli of this species being identical with those 
found in the Dasye. These ramelli appear to be also of the 
same nature as the fibres found terminating the young branches 
of other Polysiphonia, as well as Rhodomele, &c., and are pro- 
bably 'to be regarded as leaves in a very imperfect state of deve- 
lopment. In other species they are only found on young parts, 
and appear to be actively engaged in the growth of the part on 
which they are found; but in P. dyssordes they exist at every 
period, and on all parts of the frond. On old plants or old 
branches, however, they lose much of their delicacy, and become 
harsh and. squarrose. 
Fig. 1. PoLystpHonta ByssoIDEs :—the natural size. 2. Portion of the frond, 
with capsules. 3. Branchlet with tetraspores. 4. A tetraspore. 5. One of 
the byssoid ramelli. 6. Transverse section of the stem :—all magnified. 
