34 MINNESOTA BOTANICAL STUDIES. 
The walls of these cells stain more deeply than those of normal 
cells, the nuclei disappear and the chromatophores fuse together 
into a dark mass. The affected cells collapse gradually, be- 
ginning at the outer end. Often a little conical remnant of the 
shrunken cell may be seen on its basal cell. The walls and 
contents of the disintegrating cells change into a mucilaginous 
substance. 
Thus far my observations agree with those made by F. O. 
Bower.’ Bower states that the epidermal cell collapses, but 
that the basal cell persists, and that it sinks farther and farther 
into the cavity of the conceptacle, and that the lateral daughter 
cells of the central basal cell by their division form the lining 
wall of the cavity. He seeks to limit the disintegration of the 
epidermis at first to one cell and to make its basal cell the cen- 
ter of the whole process of the development of the conceptacle. 
The serial sections made by me for the investigation of this 
matter do not show that the disintegration is thus confined to 
one single epidermal cell. Occasionally several will be equally 
far advanced in decay. Naturally one or the other of these 
may decay more quickly than the rest, producing:thus a line of 
weakness and apparently a central axis about which the other 
decaying cells are grouped. 
Again, it was not found that the basal cell or cells of the dis- 
integrating epidermal cells persisted. On the contrary, they 
and several rows of cells below, perhaps five or six, share in 
this disintegration. It was frequently possible to make out the 
remains of the disintegrating cells in the mucilaginous mass to 
which they changed, and with which the cavity formed by their 
collapse was filled. 
Neither did it appear that the basal cutoffs of the epidermal 
cells produced lateral daughter cells to line the cavity. It did 
appear that they divided chiefly periclinally and somewhat 
radially, forming five or six rows of meristematic cells, the outer 
rows disintegrating and forming the cavity: the deeper ones 
persisting and finally forming the inner wall of the conceptacle 
and giving rise to paraphases and the reproductive organs. 
Bower shows figures like zg, P/7. XZ., in which the two cells, 
6 and c on either side of the central basal cell a, might suggest 
that they were the lateral daughter cells of this basal cell. But 
‘Bower. Development of the Conceptacle in Fucacere. Qr. Jr. Mic. Sci. 36. 
1880. 
