a dark red-brown, sometimes becoming purple in drying; the colouring 
matter soon given out in fresh water, to which it imparts a rosy hue. 
Substance very tender and gelatinous, soon decomposing. Odour offensive. 
The species here figured, originally defined by Mr. Dillwyn in 
the supplement to his work on the British Conferve, appears to 
be well understood by most British botanists, who are sufficiently 
familiar with its characters from the excellent specimens published 
by Mrs. Wyatt. It is pretty generally dispersed on the British 
coasts, and must be regarded as one of our commonest species of 
Polysiphonia. 1am not clear, however, that it-is equally well 
understood on the continent, and have reason to believe that it 
is known in different places under several different names ; but 
in the present state of our knowledge of the Polysiphonia, 1 
have not ventured to bring together any supposed synonyms. 
The genus is a very extensive one —and its species put on, at 
different ages, a great variety of forms. These, if gathered 
isolated one from another, or by persons who are more desirous 
of recording novelties than of tracing out the true relations of 
vegetable forms, may often be made to pass for new species ; 
while they would, if carefully watched in their place of growth, 
soon put on the peculiar characteristics of the type to which they 
belong. I know scarcely any genus in which more false species 
have been founded on imperfect specimens than Polysiphonia :— 
and this is saying much in the present day, in which the practice 
has been so largely indulged in, im almost every department of 
botany ;—but especially among cellular plants. 
The dichotomous fibres which terminate the branches of our 
P. fibrata, and which have given it its name, are by no means 
peculiar to it; but are equally characteristic of the young state 
of most, if not all, the species of the genus. On some they are 
found more abundant and more fully developed than on others, 
and in the present plant this is remarkably the case. It is to 
these fibres the aztheridia are attached, which on P. fidrata are 
frequently in great abundance, crowning every branchlet with a 
tuft of golden fruit. 
Ric, 1. Tuft of PoLystpHonta FIBRaTA :—<he natural size. 2. A branch 
5 5 .7° r 5 4 ae : 
bearing antheridia. 3. Apical fibres and antheridia. 4. A ramulus with 
imbedded tetraspores. 5. Tetraspore. 6. Ramuli with ceramidia. 7. A 
ceramidium. 8. Transverse section of the frond. 9. Articulations from 
the lower part of the stem: 10, from the middle: 11, from the upper 
part all more or less magnified. 
