THE FUSION OF VENTRAL CANAL CELL AND EGG 
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zu bezeichnen, weshalb ich sie beide Eizellen nenne. . . . Jede der beiden 
Eizellen hat einen grossen ziemlich chromatinarmen Kern mit deutlichem 
Nucleolus; der Kern ist von ungefahr gleichformigen Plasma umgegeben. 
Bald verschwindet die Zellwand zwischen ihnen, und sie liegen nun frei in 
der Bauchhohle." 
The fusion of the ventral canal cell and the egg has been reported but 
once in the Musci. In 1908 J. and W. Docters van Leeuwen-Reijnvaan 
(4) published a remarkable article on the sexual process and spermatogenesis 
in several species of Polytrichum. Briefly stated their results are as follows : 
In the gametophyte generation there are six chromosomes, which is also 
the number in the cells of the antheridium. But in the final division in the 
antheridium a reduction process takes place so that each antherozoid re- 
ceives three chromosomes. In the archegonium the division of the ventral 
cell produces a ventral canal cell and an egg which are equal in size. During 
this division a reduction process is also said to occur so that each of these 
cells receives three chromosomes. The protoplasts of the ventral canal 
cell and the egg fuse while the neck of the archegonium is still closed. After 
the cap breaks open this fusion cell is fertilized by two antherozoids. 
In this manner the sporophytic chromosome number is restored. 
In 1 91 3 Walker (9) published the results of his study on the behavior 
of the egg and the ventral canal cell in Polytrichum formosum and P. com- 
mune. More than one hundred archegonial rosettes were sectioned but 
no case of a fusion could be found. Walker thinks the appearance of fusion 
of the ventral canal cell and egg reported by the van Leeuwen-Reijnvaans 
is due to their method of fixation. 
Development of Ventral Canal Cell and Egg 
The ventral cell of Sphagnum suhsecundum generally divides late into 
ventral canal cell and egg. The division of cells in the neck is almost if 
not quite complete when this division occurs. The ventral canal cell is 
not only persistent but remarkably variable in size. As a very general 
statement one may say that this cell and its nucleus are a trifle smaller than 
the egg and the egg nucleus (figs. 2, 8). However, the exceptions are num- 
erous. Often the two are identical in size both as regards the protoplasts 
and the nuclei (figs. 3, 4), while more rarely the ventral canal cell is larger 
than the egg in both of these respects (fig. 9) . 
Shortly after the division of the ventral cell the cells of the canal row 
begin to disintegrate, but this process has not as yet been found to affect 
the ventral canal cell. The protoplast of this cell begins to round off, the 
same process having begun in the egg, the wall between the two cells breaks 
down, and we have the appearance of two well rounded eggs which soon 
come more or less in contact in the venter of the archegonium (figs. 3, 8, 9). 
About this time there may appear, especially in the upper portions of the 
venter, more or less faintly staining bodies which probably take their origin 
