as British until I gathered it m the year 1833. So many habi- 
tats have since been recorded for it, that it may be regarded as 
a generally distributed form, if not species. 
It most nearly agrees in character with C. aldida, but the fila- 
ments are coarser, and far more rigid, standing out from each 
other when the tuft is removed from the water; the colour is a 
brighter and fuller green; the ultimate branches are shorter and 
more patent, often strongly reflexed, and the general habit is by 
no means spongy. 
It appears to prefer the clearest and purest water, growing on 
the bare rock or among corallines in deep cold pools left by the 
tide, near the extreme of low water mark. Where I have seen it, 
both at Kilkee and Dingle, it could only be reached at spring - 
tides. 
Fig. 1. CLapoPHORA REFRACTA:—zatural size. 2. Portion of a filament. 
3, 4. Ramuli:—more or less highly magnified. 
