336 Cleland . — The Cytology and Life-history of 
trichogyne, but in the carpogonium. These extra nuclei are extremely 
small, insignificant structures, and they very quickly break down (Fig. 29). 
I have not found a single case where a nucleus was even doubtfully present 
in the trichogyne itself. The fact that in many hundreds of carpogonia 
and trichogynes, in all stages of growth, only a few possible examples of 
an extra nucleus have been found, convinces me that the formation of 
a trichogyne nucleus in Nemalion is not an invariable occurrence. When it 
is present, this extra nucleus is diminutive and lives only a short time, not 
even long enough, in most cases at least, to reach the trichogyne. We 
probably have here a reduction from the condition where a trichogyne 
nucleus was regularly present, to a state where it is only occasionally found. 
It will be seen from the figures that the position of the carpogonial nucleus 
in the cell bears no relation to the formation of a trichogyne nucleus. In 
Fig. 28 the division seems to have taken place below the chromatophore ; 
in Fig. 27, above it. The carpogonial nucleus seems often to rest in the 
upper part of the carpogonium, even when no mitosis occurs. 
There has been some dispute as to the presence of the trichogyne 
nucleus in Nemalion and related forms. Wolfe was positive in his assertion 
of its presence, describing it as well marked and unmistakable. Kylin, 
while describing and figuring it, stated that it is very small and visible only 
with difficulty in very young trichogynes. Kurssanow denied its presence 
entirely in Nemalion lubricant and Helminthora divaricata. Davis (1896), 
working on Batrachospermum , was the first to describe a trichogyne nucleus, 
but Osterhout (1900) and Schmidle (1899) did not find it in this form. 
Svedelius (1915) reported it in Scinaia furcellata and Kylin (1916$) in 
Bonnemaisonia asparagoides. In the tetraspore-bearing red algae the 
evidence for its presence seems to be very clear. It has been described in 
Polysiphonia as a large body which does not disintegrate until after the 
fertilization of the egg ; in Rhodomela virgata , Griffithsia corallina , and 
Delesseria sanguinea as a structure which quickly disintegrates and 
disappears. Lewis has not determined the situation for Griffithsia Bornet- 
iana ) but the probabilities are that it conforms to the condition found in 
G . corallina. 
More than one theory has been advanced concerning the origin and 
nature of the trichogyne and its nucleus. Davis (1896) regarded the 
trichogyne of Batrachospermum with its nucleus and reduced chromato- 
phore as having a certain degree of independence as a separate cell. 
Yamanouchi (1906) admitted that the trichogyne has a certain degree of 
independence, due to its possession of a nucleus, and believed that the 
multicellular trichogynes found in the Laboulbeniales illustrate a further 
development of this independence. However, he considered the trichogyne 
to have been originally an outgrowth of the carpogonium, and the trichogyne 
nucleus to represent a second female gamete nucleus now functionless. 
