388 ON ACTINOTHRIX. 
radiating from a free central mass. When young, the central mass is 
large and spherical, and the fibres are short and conical, giving the whole 
plant the appearance of a Calthrops ; as the Alga grows the filaments 
gradually elongate, become more cylindrical, that is less conical an. 
tapering, and the central mass decreases in size, until in the perfect 
plant the long filaments seem to spring from a small central dot. The 
endochrome is annulated, the rings being numerous and very narrow, 
looking as a series of coins arranged closely side by side would appear 
if placed within a glass tube. 
Actinothrix Stokesiana, n. sp. ; bright-green ; the filaments 19 or 20 
from one centre. 
Hab. Ross Bay, in used Bay, Ireland, among Cladophora. Mrs. 
John Stokes. August, 1864 
The endochrome is of a vey bright green, and the cell-wall of the 
filament forms a perfectly transparent margin, external to the endo- 
chrome and continued beyond it. The longest filaments I have met 
with are a quarter of an inch in length. 
It has been suggested that this may only be the earliest stage of 
Actinothrir Stokesiana, n. sp.—1. Plant,—natural size. 2. Plant ,—magni, i. 
outline. 3. Magnified fragment of the central mass, showing the method o 
tachment of the filaments, and the a ores of the endochrome. At e 
base o ment the continuity of the e ome is generally broken, one or 
figure. 
two separat es being almost always found ‘ace ; as shown in this fi 
