194. DopGE: RELATIONSHIPS OF FLORIDEAE AND ASCOMYCETES 
or eight cells. Arranging these forms with only one ascogenous 
cell in the order of the complexity of the archicarp we find the 
following series: Lasiobolus pulcherrimus, Ascobolus furfuraceus, 
A. immersus, Lachnea scutellata, Lasiobolus equinus, Ascobolus 
Winteri, A. Leveillei, Pyronema, Thelebolus, Sphaerotheca. 
If we compare the second and third groups above, especially 
Ascobolus carbonarius with A. furfuraceus we may get some light 
on the nature of the entire ascogonium in the latter species, that is, 
on-the question whether the part beyond the ascogenous cell is 
to be considered morphologically as a trichogyne. 
It is certainly very difficult to attempt to homologize the crosier 
and nuclear fusions in the young ascus with the odblastema and 
auxiliary cells and fusions of the Dudresnaya type, but it is clear 
that both involve the same physiological or nutritive conditions. 
After the fusion of the odblastema filaments with the auxiliary 
cells which are gorged with nourishment we find the conditions 
required for the production of well nourished filaments producing 
spores. The vegetative nuclear fusions in the ascogenous hyphae 
provide a large amount of nuclear substance to maintain the 
“‘nucleo-cytoplasmic equilibrium” of a large spore mother-cell. 
In other words the secondary fertilizations of the red algae pro- 
vide conditions suitable to the formation of groups of carpospores 
just as the hook phenomena and nuclear fusions in the Ascomy- 
cetes lead to the production of ascospores. } 
We must consider the outgrowths of the carpogonium in all 
forms of the red algae as homologous structures. The question 
as to whether or not reduction occurs at the germination of the 
fertilized egg in Nemalion is not necessarily a vital one in this 
connection. The odblastema filaments of the Dudresnaya group 
are then homologous with the sporogenous hyphae of Dermonema, 
Nemalion, etc., although they do not give rise, for example in 
Gloiosiphonia, directly to carpospores. In the Ascomycetes, 
Dudresnaya, and Gloiosiphonia both ascospores and carpospores 
are produced only after secondary fusions have occurred, and the 
suggestion is strong that the ascogenous hyphae are homologous 
with the odblastema filaments. The very short odblastema out- 
growths in Harveyella, Erythrophyllum, Prionitis, correspond to 
the long much branched odblastema of Dudresnaya, and among the 
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