40 Wisconsin Academy of Sciences, Arts, and Letters. 
slightly to form abroad base for the carpophore. The branches 
are short and branched in turn to form a knot of hyphae which is 
somewhat similar to the tangled mass formed at the base of the 
carpophore of Coprinus. But the cells are shorter and straightcr 
so that the hyphae are not so matted and difficult to trace. Above 
the tangled hyphae at the base, the branches gradually assume 
a more vertical direction. They are still interlaced like the 
meshes of a net which has been pulled out lengthwise. Near 
the top of the button the number of branches increase and in¬ 
stead of continuing in a vertical direction they spread out radi¬ 
ally. This is the first indication of a pileus. The outer branches 
of the central system of hyphae are not so closely interlaced but 
form a loose open network covering the pileus and stipe still 
further to the exterior. The surface of the button is formed 
by a layer of nearly straight hyphae. They arise as lateral 
branches near the base of the button and covering the entire 
surface, disappear among the hyphae at the apex of the pileus 
where the loose network of branches is thicker than at the sides. 
These hyphae are formed of long slender cells with very little 
protoplasmic contents. The shape of the cells and the direction 
of growth of the hyphae differentiate this outer layer very 
sharply from the tissues in the interior of the button. All of 
the cells are binucleated. The nuclei are large and have a 
nuclear membrane, a small nueleole and very finely granular 
chromatin. 
At this time the young carpophore is an oval body and as 
indicated its tissues can be separated roughly into three distinct 
portions. The central portion formed of closely interlacing 
hyphae, which may be still further divided into the base 
of closely packed hyphae, the more vertical intervening hyphae 
from which the main portion of the stipe is formed, and 
the rather loosely spreading mass at the top from which 
the pileus develops. Second and outside of this central portion 
there is a poorly defined layer of loosely tangled hyphae which 
will untimately form the veil above and the outer covering of 
the stipe below. This layer is not sharpelv separated from the 
central portion and is formed by lateral branches from that 
region. The third and outer portion is a layer of parallel hyphae 
