1906] YAMANOUCHI—POLYSIPHONIA VIOLACEA 415 
which is in the gamete. This extra nucleus has an important relation 
to the development of the trichogyne, which consequently is much 
more than a mere cytoplasmic extension from the carpogonium; for 
having a nucleus it may possess the possibilities of a somewhat exten- 
sive development. This is perhaps the explanation of the multi- 
cellular trichogynes of the lichens and the Laboulbeniaceae, which 
in some forms of the latter group are extensively branched. 
The passage of the sperm nucleus through the trichogyne into the 
car pogonium.—The nucleus of the carpogonium increases in size as 
the female cell matures, while the nucleus of the trichogyne remains 
about the same size as when it was formed (fig. 104). The sperm 
becomes attached to the tip of trichogyne (fig. 105). The walls 
between the two structures dissolve, and the contents of the sperm 
flows into the trichogyne (jig. 106). The sperm nucleus consists of a 
number of deeply staining bodies (about 20), which are chromosomes. 
The nuclear membrane if present must be very delicate, for it could 
not be positively recognized (figs. 106-108). The deeply staining 
‘petm nucleus in the trichogyne is in sharp contrast with the smaller 
trichogyne nucleus whose chromatin content stains weakly. The 
sperm nucleus moves downward, passing the trichogyne nucleus (jigs. 
707, 108), and enters the carpogonium. The female nucleus in the 
“atpogonium, which until this time lay at the bottom of the cell, 
seems to move upward a short distance as if to meet the sperm nucleus 
(fig. 109a). The two gamete nuclei are strikingly dissimilar at the 
time of union, the male consisting of a densely packed aggregation of 
chromosomes, while the female is larger and in a typical resting 
Condition, with chromatin distributed over a linin network (fig. r09a). 
he trichogyne nucleus may still be recognized after the sperm 
nucleus has passed into the carpogonium. However, the cytoplasm of 
the trichogyne soon shows signs of disorganization, first at the tip, 
and a little later the trichogyne nucleus breaks down. When the 
male nucleus is in contact with the female and becomes somewhat 
Pressed against it, the cytoplasm of the trichogyne has probably 
always separated from the carpogonium and the trichogyne has begun 
to shrivel], 
Formation of the auxiliary cells Parallel with the fusion of the 
8amete nuclei there takes place the development of a set of auxiliary 
