FLUSTRA. 349 
portions of the segments were of a pinkish colour, from 
the cell being filled with living polypes. This species does 
not appear to have any of the pleasant flavour which cha- 
racterizes F. foliacea. 
** With cells on one side only. 
4. Frustra carBasea, Dr. Skene. 
Hab. Aberdeen, Skene; Leith, Dr. Coldstream; coast 
of Durham, J. Hogg; coast of Berwickshire, Dr. John- 
ston; Bootle, rare, Mr. Tudor; Dublin Bay, rare, Mr. 
M ‘Calla; Stonehaven, Lady Keith Murray; on the fisher- 
men’s nets at Newhaven, in some abundance, D. L., jun. ; 
Peterhead, rare, Mr. Peach. 
It is very easy to distinguish this from any of the pre- 
ceding species, from having the cells confined to one side. 
The substance is thin, the colour brownish, and the surface 
glossy. It has no tufted tubular roots; the segments ex- 
pand, and are rounded at the top. It is about two inches 
in height, and, in proportion to its height, broader than 
either F. foliacea or F. truncata. Even on the Leith 
shore it is comparatively of less frequent occurrence. When 
I told my lamented friend, the late Dr. Patrick Neill, that 
I had got great abundance of F. foliacea and F. truncata at 
Seafield—*“ But did you get carbasea?” said he. “ For 
