1906] YAMANOUCHI—POLYSIPHONIA VIOLACEA 407 
similar to that in the tetraspore that it seems best to point out only 
the marked differences between the two. The delicate linin network 
within the nucleus passes into a coarse chromatin reticulum upon 
which chains of chromatin granules appear here and there (figs. 16a—- 
16c), and these are prochtomosomes, as illustrated in the preceding 
figures of the tetraspore (figs. 2a-2c). The number of prochromo- 
somes, however, is 40, and consequently double the number in the 
germinating tetraspore. The 4o prochromosomes grow more and 
more homogeneous in structure and finally become elongated chromo- 
somes (jigs. 17a, 176). The weakly staining linin network disappears, 
but short threads remain attached at the ends of chromosomes. 
The kinoplasm surrounding the nuclear membrane becomes accumu- 
lated at the two poles of the nucleus, where a centrosome-like body 
may always be found (jig. 18a), and this accumulation of kinoplasm 
proceeds still further until there are two conspicuous centrosphere- 
like structures differentiated at metaphase (fig. 19). The spindle 
is somewhat larger and broader than that in the tetraspore, because 
of the double number of chromosomes (fig. 19). The polar view of 
that stage (fig. 20) clearly shows the number 4o. 
The nucleolus fragments during metaphase, the portions lying 
beside the spindle (ig. 19) and sometimes remaining until anaphase, 
after which they disappear. The behavior of the daughter chromo- 
somes after anaphase is the same as during mitosis in the tetraspore; 
the groups of daughter chromosomes gather at the poles of the spindle 
(fig. 21) and become surrounded by granular kinoplasm (fig. 22). 
At the time of the formation of the nuclear membrane, the chromo- 
Somes may still be recognized and estimated as 40 (figs. 234, 23b). 
The daughter nuclei increase in size by the secretion of nuclear sap 
(figs. 24a-24¢), and finally the chromatin becomes distributed over a 
linin network in the resting nucleus (fig. 25). The germinating carpo- 
Spore becomes divided by a cleavage furrow in a similar manner to 
that of the tetraspore. 
The second and third mitosis in both germinating tetraspore and 
Carpospore were also studied, and they were similar to those of the 
first divisions, showing always the two essential differences in the 
number of chromosomes. 
