a brownish red, sometimes purplish. Substance membranaceous, adhering 
to paper. On being re-moistened, the frond exhales the odour of violets. 
~ 
A common species, but variable in its characters, and gradually 
approaching C. voseum on the one hand, and C. Hookeri on the 
other. Our plate represents what we regard as the typical form, 
or idea, of the species. It is remarkable for the short, awl-shaped, 
simple pinne, beaded, on the inner face, with globose tetraspores. 
From this I formerly distinguished C. Grevillii by a plumule of 
broader and shorter outline, whose uppermost pinne were pin- 
nulate at top. A more intimate acquaintance with the species 
of this genus, and an examination of a profusion of specimens 
exhibiting numerous variations from the original type of C. poly- 
spermum, but all more referable to it than to any other species, 
have made me cautious of admitting the value of the characters 
I had formerly considered belonging to C. Grevillii. I now 
regard that species therefore as an imperfectly developed form of 
C. polyspermum, whose uppermost pimne are passing into the 
state of plumules. | 
C. polyspermum more frequently grows on the coarser Pucz 
than any other species, and sometimes clothes them with densely 
set, globose tufts, which in old age become blended together, 
concealing the greater part of the plant on which they grow. 
The finest specimens I have received were collected at Mount 
Edgecombe, by my liberal Plymouth correspondents, Messrs. 
Hore, Rohloff, and Cocks. 
Fig. 1. CALLITHAMNION POLYSPERMUM :—of the natural size. 2. Portion of a 
branch, with four plumules. 3. Pinne with tetraspores. 4. Plumule 
with favelle. 5. Favelle detached. 6. Pinna with antheridia? 7. Joints 
from a branch. 8. Joints from the lower part of the stem :—all more or 
less magnified. 
