confluens and the Morphology of the Ascocarp. 367 
formed. The polar asters are persistent after the last division 
as in other cases I have studied, and when the beak is formed 
on the nucleus the aster lies at its tip. The structures at this 
stage in Pyronema are quite small, but all the principal stages 
in the transformation of the aster into a plasma-membrane 
for the ascospore can be readily distinguished. Fig. 40 shows 
an exceedingly common stage in which the beak is formed, 
and the aster is apparently flattened somewhat against the 
wall of the ascus. In the case of three of the nuclei in this 
ascus the axis of the beak was so nearly vertical to the plane 
of the section that it is not represented in the figure. The 
nuclei are in the resting condition and fully developed. They 
contain a single nucleolus as a rule, and the chromatin is in 
the form of irregular granules and rods, or even threads. 
The dense mass of protoplasm in which the nuclei are lying 
is entirely without indication of its future differentiation into 
spore-plasm and epiplasm. At the upper end of the ascus 
above the region where the spores are to be formed it is 
loosely spongy and vacuolar in texture. The same condition 
is found in the ascus below the spore-bearing region, but is 
not shown in the figure. 
Fig. 41 • shows a later stage in the spore-formation also 
very common in Pyronema ,, though not so common in the 
forms hitherto studied. We have here a stage when the spores 
are about half surrounded by the folded back rays of the 
aster. The rays are already fused to a membrane about 
the point of the nuclear beak as shown by the slight plasmo- 
lysis in the case of the lowest of the forming spores in the 
Figure. In two cases here also the beak does not appear 
because it stands too nearly vertical to the plane of the 
section. In both these cases, however, portions of the forming 
plasma-membrane appear in the positions where they are to 
be expected partly encircling the nuclei. The amount of 
material in the asters and developing membranes in this ascus 
is plainly much greater than is present in the stage repre¬ 
sented in Fig. 40, and indicates, as I have pointed out 
before ( 16 ) that new kinoplasmic material may be formed 
