6 BOTANICAL GAZETTE [JANUARY 
cells which it connects. I have not observed the development 
of these clamp connections in Hypochnus, but in the mature 
condition as they are universally found in my material they 
show but one septum, and that apparently on the cell from 
which the clamp-tube originated. The significance of these 
structures is not clear. Presumably they facilitate the transfer 
of excess food materials and moisture from one cell to another, 
but just how they are adapted to this function is not evident 
from their structure. I have not observed in Hypochnus the 
granules or plates on the septa between adjacent cells which are 
so common in many Basidiomycetes and Ascomycetes (5, 7), 
and which probably indicate the location of some sort of pores 
for communication between the hyphal cells. In Coprinus, as 
we shall see later, such plates are present in great abundance, 
and have a very characteristic appearance. 
The mycelial cells of Hypochnus vary considerably in length, 
though of fairly constant diameter in the mature mycelium. 
A cell of about average proportions is shown in fig. 7. In the 
specimens studied the hyphae formed no dense wefts or strands 
in the substratum. On the whole it seemed rather loose and 
sparse. The vessels of the decaying wood with their large — 
empty cavities afforded a favorable opportunity for studying the 
hyphal cells, the hyphae cutting through these cavities in all 2 
directions, but never filling them densely. The mycelial cells — 
are practically without exception binucleate. The two nuclei — 
generally lie rather close together and near the center of the — 
cell, but they may be at opposite ends, or otherwise placed in — 
the cell. /ig. zo shows that, however the pair may be located — 
in the cell, they are generally rather close together. These — 
nuclei show, in well-stained preparations, a nucleole and chro- — 
matin sharply differentiated, and are sharply bounded by 4 
nuclear membrane. 
Fusions (6), such as have been described by many observers 4 
between cells that are near together or in contact, are quite © 
common in Hypochnus. There is no clear evidence that in this — 
case they have any other significance than as channels for the © 
