ON PROTOPLASMIO CONTINUITY IN THE FLORIDEX. B5 
connecting the mass which is subsequently converted into tetra- 
spores, with that of the cell, of which it forms a lateral appendage. 
t will be obvious that this is a case of protoplasmic continuity of 
a like nature to that which obtains in the vegetable cells. It may 
he added that the tetraspores themselves are for a time connected 
together in a similar manner. 
In illustration of these details Plate 243, figs. 1, 2 may be con- 
ted. From this it will be seen that at the point ‘where the con- 
toma thread passes through the transverse partition there is 
‘a small lenticular body, whose optical appearances differ from those 
of the protoplasm. It is so small in the Callithamnions that it is 
not easy to determine its true natnre, but from what occurs in 
hey Rhodosperms, where the connections are on a much lar er 
scale, there is reason to believe that it is a geek ae thickening of 
the cellulose wall through zt the thread pass 
still more remarkable exhibition of yea pIASIIG continuity 
than the preceding is that pheahise by Callithamnion arbuscula. 
Here, as previously Sie ancd the Bupes is densely corticated, and 
the whole lab attains larger dimensions. The organ nisation of 
ns. this be be me 
which is represented on Plate 248, fig. 3. This shows that the 
cells of the central portion of the stipes are of considerable size, 
and are clothed with a dense felted mass of cortical filaments, 
oblique direction. The protoplasm of each axial cell is unmis- 
Sakiily connected with that of the cells stots ‘ead below it. The 
nature of that connection is at times peculiar. The protoplasm of 
caeh cell is ange more or less about the middle of the cell, and 
is dilated at the ends, as described in Callithamnion roseum. The 
dilated ae occasionally appear to be hollowed out, like the bell-end 
of a trumpet, and from the centre of the hollow the connecting cord 
of eekoplaain passes onwards to the transverse wall. At the point 
where the cord passes through the partition it is enclosed in a sort 
of thickened ring or collar, and in some instances the cord presents 
_ a striated appearance 
_ _. The very thick cortex is as remarkable from the point of at : 
_ this paper as is the central siphon, The filaments of which i 
composed exhibit continuity throughout, and present a aie: 
characteristic appearance. Some idea of this may be gathered 
from fig. 8, but it is hardly possible to do eur to it in a drawing. 
_ With scarcely an exception the fine c ds are provided 
a small collar, and this usually re remaina han the thread is 
__ A further point to be noticed is that similar connections exist 
btsncan, th the al cells of the stipes and those of the prim 
_ branches, and between the cells of the primary branches and those 
of the secondary branches, so that from the base or point of 
_ attachment of the frond to the freely growing tips of the ultimate 
branches the ete of the protoplasm is in the normal con- 
dition, unbroken 
