FAULL: DEVELOPMENT OF ASCUS. 
85 
second and between the second and third spindle stages. But they 
either reappear or else are formed anew in the early prophase stages 
of mitosis. 
The spindles of this generation lie in about the same plane as that 
in which the first lay, and end to end in a straight line. They are 
more easily studied than was the first, and though not different from 
it in the main, yet exhibit certain peculiarities that readily dis¬ 
tinguish them. Thus, unlike the first, they occupy a proportion¬ 
ately larger part of the space within the nuclear wall, they are not 
eccentrically placed, their astral rays are somewhat coarser, and there 
is a sort of mantle formed about the intranuclear part of each (pi. 7, 
fig. 16). This mantle, the definite character of which was not 
determined, adheres to the middle part of the spindle for some time 
after the nuclear wall goes to pieces. In all probability it is not a 
mantle of fibers belonging to the spindle, for figure 17 (pi. 8) indi¬ 
cates that there is no connection with the centrosomes. In the ana¬ 
phase stages the spindle elongates, at first giving to the nuclear wall 
an oval shape, and after the disappearance of the latter, still contin¬ 
ues to extend. The stretching or growth of the fibers, whichever it 
may be, is the most pronounced in this case of all the three mitoses 
occurring within the ascus. Finally, the threads of the spindles 
vanish, and the four daughter nuclei form, and pass into a resting 
condition, as we saw for the nuclei that preceded them. They 
change their relative positions, however, so that, while in practically 
the same plane, they are not in a straight line. 
Coming now to the last mitosis it is to be noted that the phenom¬ 
ena up to the anaphase stages are the same as have been described for 
the second division, and they are as readily observable. The spin¬ 
dles may lie side by side or at an angle to one another, but all are 
in about the same plane (pi. 8, fig. 19). Interest centers in the 
events subsequent to the spindle stage, for before the daughter 
nuclei reach the resting state the young spores are delimited. 
We have already seen that one of the features of the anaphase 
stages of the first two mitoses is an elongation of the spindle fibers. 
The same is true of the third. The result of this elongation in the 
last case is to bring the young daughter nuclei against or near the 
upper part of the plasma membrane that surrounds the dense proto- 
.plasm. Thus in looking down on the upper end of the ascus as 
represented in figure 21 (pi. 8) the centrosomes of five nuclei could 
