340 Cleland . — Lhe Cytology and Life-history of 
chromatophore may be seen. At first it is nothing more than a body of 
somewhat denser consistency than the surrounding cytoplasm, and, in well- 
fixed material, is in contact with the cytoplasm. As growth proceeds it 
becomes more distinct, following the same line of development as described 
escaping spore possesses a very 
distinct chromatophore, which is 
in the condition corresponding 
to Fig. 8,/. 
Immediately after fertiliza- 
tion, the chromatophores of the 
upper stalk-cells of the carpo- 
genic branch begin to show signs 
of disintegration, and here and 
there in the cytoplasm of these 
cells appear a number of densely- 
staining granules of varying size, 
which have probably been cor- 
rectly interpreted by Wolfe as 
masses of reserve food material 
(Fig. 4 6). As the cystocarp 
develops, this process spreads to 
the lower cells of the stalk and 
the amount of material appears 
greatly to increase in the upper 
cells. The cells of the stalk 
then begin to fuse together by 
a widening of the connexion 
between them. The process begins at the top and progresses downward, 
resulting in one large fused cell, containing much reserve food material and 
in which the nuclei and chromatophores gradually disintegrate (Text-fig. 3). 
Mitoses in the Cystocarp. 
It is in the developing gonimoblasts that the details of mitosis can best 
be studied in Nemalion. This is due to the relatively large size of the 
nuclei and to the rapid growth and consequent abundance of figures. 
Every mitosis from first to last can clearly be followed. 
The first indication of prophase is an increasing prominence of the 
linin network of the nucleus and the development, where the threads join, 
of numerous small aggregations of material, giving to the thread system 
a knotted appearance (Fig. 51). These bodies gradually grow larger and 
more prominent (Figs. 52, 61), but the threads themselves never become 
very distinct. As the bodies increase in size, it is evident that they also 
become fewer in number (Figs. 53, 54, 62). The threads connecting 
for vegetative filaments (Fig. 8). The 
Text-fig. 3. A cystocarp developing its first 
carpospores, showing the withering trichogyne, con- 
dition of the chromatophore, the fusion of the stalk- 
cells, and food particles in the stalk, x 1056. 
