408 Cutting. — On the Sexuality and Development of 
any indication of a loss of contents. 1 The cells in these regions at the 
different stages before and after the formation of the pad were carefully 
studied and compared, and neither was there any sign of nuclear migration, 
nor were there any differences noticeable in the contents, either cytoplasmic 
or nuclear, between these stages, but those which could be accounted for by 
the gradual increase in size of the cells of these regions. There was no 
sign, therefore, of a nuclear migration from these sources. The fusing 
nuclei very probably belong to the cells of the ascogonium only. 
The next point to determine was whether the nuclei in these ascogonial 
cells were capable of fusing only with nuclei from another ascogonial cell or 
whether they only fused with others of the same cell, or again, whether they 
fuse indiscriminately with any ascogonial nucleus. Young ascogonia were 
examined in which the pads were still present, and it was found that 
fusions took place even in these young ascogonia (Fig. 5). If we neglect the 
possibility of nuclei migrating previously to the formation of the pad and, 
indeed, there seems to be no reason whatever for supposing this process to 
have occurred ; it must be admitted that the nuclei in any one ascogonial 
cell are able to fuse with one another. When the cells are in open con- 
tinuity, however, there is nothing to prevent nuclei wandering freely about, 
and I am strongly of the opinion that then the nuclei fuse indiscriminately, 
though, in the absence of any differentiation between the nuclei of the 
different cells, there can be no positive proof. 
The Ascogenous Hyphae. 
Some time after the nuclei of the ascogonium have begun fusing, and, 
as far as could be ascertained, soon after the formation of the secondary 
perforations, the ascogenous hyphae begin to be developed. It has already 
been mentioned that no special central cell is differentiated, as in Ascobolus 
furfuraceus ; similarly here no special cell gives rise to ascogenous hyphae. 2 
In some ascogonia two, three, or four cells have been seen to take part 
in their formation. I have only seen one ascogonium in which there are 
traces of ascogenous hyphae being given off by all the ascogonial cells, here 
four in number (Fig. 14). Whether this is the usual process or not could 
not be satisfactorily ascertained, for as the ascogenous hyphae soon lose 
their connexion with the ascogonium, and as the cells probably do not 
all begin forming ascogenous hyphae at precisely the same time, this 
particular point is difficult to elucidate. Cells, however, from all portions 
1 Harper records (20) that in Pyronemci the nuclei move over from the antheridium to the 
ascogonium leaving behind most of the cytoplasm. 
2 Dangeard (10) mentions that in one of his sections of Ascobolus glaber he thought that two 
ascogonial cells were giving rise to ascogenous hyphae, but he is not quite sure of this. From his 
figures it would appear that the ascogonial cells in this species are very similar in size, and it is 
possible that his observation was correct. 
