343 
times occupy nearly the whole upper side of the cell of the branch. — The quoted 
differences in the structure of the antheridial clusters of the various plants referred 
to C. byssoides suggest that different species have been confounded under this name. 
The carpogonial filaments are borne on the upper end of joints bearing a branch 
on the opposite side. They are, as in the other species, composed of four cells ar- 
ranged in a zigzag line. There are usually two auxiliary mother cells, but sometimes 
there is only one, a,, from which the 
carpogonial branch is given off, while a; 
is wanting (fig. 269). The growth of the 
procarp-bearing cell is arrested during| 
the development of the cystocarp and this 
cell is therefore much shorter than the 
other cells in the filament, when the 
cystocarp reaches its definite size, but 
it has often more protoplasmic contents. 
The fertilisation and the development of 
the gonimoblast has quite recently been 
described by Kyrın (1923 p. 56) and 
found to be as in C. corymbosum as de- 
scribed by OLTMANNS. The gonimoblasts 
are lobed; the lobes are at first cylin- 
drical, then conical (fig. 268), and finally 
rounded, ovate (fig. 270). At maturity there 
is usually a longer end-lobe and a shorter 
side-lobe, both issuing from a large cell, 
and sometimes furthermore a small supple- 
mentary lobe derived, as shown by Ky in, 
from the auxiliary cell. In some cases the 
lateral lobe is not developed, and the goni- 
moblast is then much like that of C. roseum. i å Fig. 205 } x 
£ Callithamnion Furcellarie. Two sporelings from sown te- 
The procarps were met with in Juneto Sep- traspores, 4 weeks old. 47:1. 
tember, the cystocarps in July to October. 
Tetraspores sown in July at Frederikshavn immediately germinated. 4 days 
later the sporelings were partly unbranched, about 10- to 13-celled, partly more or 
less branched. After four weeks they had grown much longer and variously bran- 
ched but sterile (fig. 271). Filaments having the character of rhizomes were frequently 
given off from the basiscopic end of the cells, and these rhizomes produced erect 
filaments. In fig. 271 to the right one rhizome is given off from the basiscopic end, 
another from the acroscopic end of the same cell, but this cell is perhaps the ori- 
ginal spore cell. 
C. Furcellarie has been met with in the months of May to October. The spores 
produced in summer and autumn are able to germinate immediately and give rise 
44* 
