The Origin and Development of the Apothecium etc. 
395 
suggests that there has boen no diminution in size. Again it seems not 
improbable that one of the two is a male nucleus. The cross walls of 
the ascogone continue to be resorbed until there are only traces of theni 
left. While the cross walls are disappearing, there is a migration of 
the nuclei so that some cells are without a nucleus and with little or no 
cytoplasm while others are multinucleate. Sometimes in at least a part 
of the ascogone there are binucleate cells the nuclei of which nray origin- 
ally liave been in adjacent cells (Fig. 25, PI. XXXII). Such cases suggest 
a process like that which occurs in Ascobolus (Welsford, 87), in which 
after the cross walls of the ascogone liave beeome broadly perforated 
there is a migration of the ascogone nuclei followed by a fusing of the 
latter in pairs. In Ascobolus, all the nuclei migrate to one cell from which 
the ascogenous hyphae arise. I am not convinced as yet that tliese nuclei 
which I sometimes find in pairs fuse; at least I have seen no perfectly 
clear case of a nuclear fusion. In some ascogones the nuclei are so close 
together that fusion is strongly suggested, and from some preparations 
it is impossible to be certain that such a process is not occurring. The 
large size of the nuclei shown in Figure 25 at a and b might suggest that 
each of these nuclei is the result of a fusion of two nuclei. I have noted 
that the nuclear membrane always stains very lightly, which makes it 
very difficiüt to be certain of nuclear fusion; then too, we cannot be 
certain that these nuclei are all ascogone nuclei. To be certain of this 
we must know what happens in every cell of the ascogone — which is 
not always easy. It is not safe to conclude that the pairs of nuclei in 
the ascogone shown in Figure 25 are female, since branches of the ascogone 
have been formed at c and at d. I have not succeeded in following 
these branches. All of the cross walls of the ascogone are broken down 
and so any particular nucleus might be supposed to be either male or 
female. It is evident that this part of the ascogone which is branched 
lias developed most rapidly. 
The number of nuclei in these nucleated parts (originally cells) of 
the ascogone is increased by division so that groups of smaller muclei 
result. Judging from the number of these smaller nuclei, there ean 
liardly be more than three or four divisions before the ascogenous hyphae 
are formed. Figure 50, PI. XXXIV at a, shows a group of twelve nuclei 
in a part of the ascogone which is just beginning to give off a branch. 
In this group two of the twelve nuclei are each about twice the size of 
any of the other ten. It is possible that these two will divide again shortlv. 
At b in this same ascogone is a group of eleven nuclei each of which is 
about as large as each of the two larger ones in the group at a. There 
