338 
Fig. 262. Fig. 263. 
Callithamnion Furcellariæ. Bases of plants with intra- Callithamnion Furcellariæ. À, basal part of plant. B, creep- 
matrical and extramatrical descending filaments. 4 45:1. ing filaments from the foregoing year. A new erect 
B 95:1. shoot has broken forth from the remains of an erect shoot 
Callithamnion Furcellariæ. À, cell showing 
the nucleus and a number of the chro- 
matophores. B and C, cells connected by 
a broad bridge of protoplasma at the 
periphery. À 195:1. B, C 270:1. 
from the foregoing year. A 70:1. B 80:1. 
on the same joint, diverging from one another at 
an angle of a little over or a little under 90°; the larger 
one entered into the spiral. For more details see my 
paper (1920 pp. 49—58). 
The principal axes are distinct and straight or 
only a little bent in zigzag. The ramification is thus 
distinctly monopodial but sometimes it may be some- 
what corymbose, thus reminding of that of C. co- 
rymbosum. The length of the cells in proportion 
to the breadth is rather variable but usually con- 
siderable, varying from 4 to 12, rarely up to 17, but 
in the lower part of the main axis the cells are 
shorter. 
In the lower part of the principal shoot single 
descending filaments occur, being partly intramatrical, 
partly extramatrical, but in the first case not forming a 
continuous cortical layer. The intramatrical ones may 
