The Origin and Development of the Apothecium etc. 
393 
the terminal cell) of this carpogone, at b, there are two nuclei which ciiffer 
greatly in size. The larger one I take to be the primary nucleus of the cell. 
It does not seem likely that tliis nucleus could have divided and the growth 
of the daughter nuclei liave been so unequal. If the two are not sister 
nuclei, then the sm aller nucleus must have come from another cell. It 
is also probably not the result of the division of a nucleus in an adjacent 
cell, because all the nuclei in these cells are of very much the same size 
with the exception of course of the small nucleus in question. All of 
the septa distal to this binucleate cell are perforated, although the 
perforations are much more evident in some cases than in others. It 
seems probable, tlrerefore, that this small nucleus is a male nucleus. If 
my conclusions be eorrect, it follows that either the spermatium con- 
tained two nuclei which have passed down the trichogyne, or eise that 
the one nucleus originally present in the spermatium has divided. 
But the question is at onee presented with which of the nuclei in 
all the cells of the ascogone will the male nuclei fuse, and why should 
they not remain in the more distal cells of the carpogone and fuse with 
some nucleus or nuclei there? The nuclei in the several cells next to 
the terminal cell take no further part in the development of the fruit 
body. These cells now begin to exhibit characteristic ehanges. The 
cross walls, which up to tliis time have appeared thin and sharp in out- 
line, now apparently become gelatinized and very much thickened. This 
thickening is usually greatest in the center of the septum, so that the 
walls become biconvex (Fig. 30, PL XXXII); sometimes, however, they 
are biconeave (Fig. 33). This process begins in the most distal of the 
trichogyne septa and progresses toward the ascogone. In the more distal 
cross walls, the perforations earlier present have been entirelv closed 
by a thick plug of this gelatinous material wliile the cross walls nearest 
the ascogone appear as thick gelatinous plates with broad central open- 
ings. Sometimes this mass is thic-ker on one side of a septum than on 
the other. It is possible to see clearly the extent of the former opening 
because the remains of the cross walls on either side of the opening appear 
denser than the gelatinous substance which surrounds them (Fig. 28). 
In still older trichogynes the denser cross walls disappear and leave a 
clear hyaline zone (Figs. 27, 29), which after a time mav extend entirely 
across the gelatinous plug. The cross walls nearest the ascogone appear 
as thick gelatinous plates with broad central openings. The figures show 
these gelatinized walls in median optical seetion, exc-ept in those cases 
in which a sharp bend of the trichogyne upward or downward has made 
it necessary to draw end views of them. In my preparations made with 
