1 6 Brannon . — The Structure and Development of 
In Schmitz’s discussion of the origin of the female sexual 
cells of the Florideae, he states that without exception they 
develop from the end-cells of shorter or longer side-branches 
of the whole system of ramification of thallus-filaments ; that 
these branches are formed sometimes as secondary side- 
branches subsequently to the formation of other ramifications ; 
and that, in all cases, the female sexual cell, the carpogonium, 
is formed from the end-cell of the side-branch by permitting 
a process to project from its apex which develops into a more 
or less long hair-like trichogyne. 
As has been shown in the foregoing description of the 
origin of the procarpium and carpogonium, Grinnellia agrees 
with many of the Florideae in the development of these 
organs. 
It was impossible to discover antherozoids fusing with the 
trichogynes of freshly collected material, therefore several 
young female fronds were placed in a dish of water and 
•covered with antheridial plants. The same degree of care 
was observed with respect to the change of filtered sea-water 
at stated periods and the excess of light and heat as had been 
found necessary in the successful germination of spores and 
the preservation of living Grinnellia plants. Very satisfactory 
results followed, and several cases of fusion and partial fusion 
were found in sections of specimens artificially brought 
together. 
The carpogonium is fertilized by the fusion of one or more 
antherozoids with the trichogyne (Fig. 19 a). It was im- 
possible to identify the nucleus in the antherozoids, and 
equally difficult to determine whether the trichogyne possessed 
a nucleus. Hence no union of nuclei was observed when the 
cell-contents of the antherozoid were intimately associated 
with those of the trichogyne. In the latter there were 
individual and grouped particles, which took a deeper stain 
when treated with Delafield’s haematoxylin than the sur- 
rounding non-granular substance. 
In somewhat older specimens the trichogyne is separated 
from the fertilized carpogonium by a cellulose plug which is 
