330 Wisconsin Academy of Sciences^ Arts, and Letters. 
tion occurred at this early non-septate stage, it would not be neces¬ 
sary for the nuclei to pass through pores from cell to cell. All 
the preparations indicate that fertilization occurs during the non- 
septate stage, for later stages show the nuclei paired in the cells 
of the coil of the ascogonium, figs. 11, 12 and 13. 
An effort was made to discover if nuclear fusion occurred in 
the ascogonium. Sections cut from the coils as they formed and 
from the perithecium after it is fully mature, including the inter¬ 
mediate stages, failed to give evidence of funsion. Nuclei are 
found in pairs, fig. 12, and later in aggregates of four, fig. 23c. 
Figs. 7, 8 and 11 show sections of the perithecium. The ascog¬ 
onium is coiled, four to six cells being visible, and the nuclei are 
paired. Fig. 8 shows the trichogyne still attached and the nuclei 
migrating toward the ascogonium each cell of which has paired 
nuclei. In none of the preparations of these early stages, how¬ 
ever, was nuclear fusion apparent. Figs. 10, 11a and 11b indicate 
the condition of the structure. The basal or stalk cells are still 
visible and extend toward the periphery of the perithecium, while 
at the opposite end of the coil the trichogyne emerges. The stalk 
may be regarded as the basal remnant of the original branch. At 
the time the coil originates it appears as if two branches were 
concerned, one enlarging to form the ascogonial coil. What the 
function of the other hypha is could not be determined. It may 
be nutritive or sexual, but it is impossible to follow the develop¬ 
ment accurately as the vegetative hyphae enclose the coil and form 
a dense covering. The diameter of the perithecium is often 150 
microns and one section or series of sections is difficult to inter¬ 
pret. The ascogonium is coiled and all portions' do not lie in the 
same plane. In some figures, 11a and 11b, the coil is shown very 
distinctly. The cytoplasm is stained very densely and the nuclei 
stand out remarkably well. Each cell is binucleate, the cytoplasm 
is slightly granular in each cell. Fig. 12 also indicates the con¬ 
dition of the ascogonium when the nuclei are paired. As the peri- 
thecia enlarge and when they are from eight to nine weeks of 
age in cultures, the cells seem to increase in number and sections 
often show four nuclei in one cell, figs. 19, 23b and 23c. The 
cells of the coil increase in size until the perithecium has reached 
its maximum diameter. Following the four nucleate stage a 
large number of cells appear and extensive branching is apparent. 
There is considerable evidence to indicate that the large cells of the 
ascogonium branch, the branches become septate and form the asci, 
