was based on the same plant, because it is well known that the gills 
of Lepiota Morgani are white until the spores ripen. Certain it is 
that the figure of Agaricus subtomentosus is a perfect representation 
of the plant, much better than any that have appeared in this country. 
We presume in view of these facts that priorists will have to call our 
American plant “ Eepiota gracilenta,” and we would consider it very 
unfortunate if we felt obliged to do the same. We do not undervalue 
the historical importance of the information Prof. Bresadola has 
kindly given, although we feel it would be a misnomer to call a plant 
“ slender,” when in reality it is the largest and most obese of our 
species. 
25 7—COPRINUS RADIANS. 
Several years ago while at Boston I found some of our Myco- 
logical friends puzzling over a little species of Coprinus which had been 
found in a tuft of Ozonium. They were surprised when I told them 
it was the most common species that we have in our woods around 
Cincinnati, and that it usually grows in this Ozonium. It has been a 
question to me for many years what the connection is between this 
Coprinus and the Ozonium. 
If it were only occasionally that we find the two associated, we 
might think that in these cases the Ozonium was merely an accidental 
host. In certain seasons of the year. Coprinus radians grows very 
common in the woods around Cincinnati. We have noted it hundreds 
of times, and in almost every instance it grows from a patch either 
small or large of brown Ozonium. 
It is particularly partial to Elm, and an elm tree that has fallen 
only a year or two and still retains its bark is a favorite habitat for 
the plant. We have counted over a hundred specimens growing from 
cracks in the bark of a fallen elm. 
Ozonium auricomum, as named by Link, is very common on fallen 
branches of elm, forming a dense cushion of coarse brown fibers. It 
looks not unlike coarse brown wool. You find it in Engler and Prantl 
(p. 517), under “Sterile Mycelium of doubtful belongings,’’ and 
described with “fructification unknown.” It was considered by Fries 
as a sterile mycelium. Rarely do we find it in the proper season in 
this locality that a number of specimens of Coprinus radians do not grow 
from it. The question that I have tried to solve is, “ Is it the myce¬ 
lium of this species of Coprinus?” The constant association of the 
two, and the fact that no other species of Agaric grows in the Ozonium 
in our locality, strongly tend to this conclusion. I am not expert 
enough with the use of the microscope to trace the connection between 
the two, but Prof. Bresadola writes me “Dr. Penzig has a study in 
1880 of Ozonium and Coprinus, and has reached the conclusion that 
the Ozonium is the mycelium of the Coprinus. I have examined your 
specimen and find nothing to confirm the opinion of Penzig. I find 
only points of contact, but I have not been able to trace the hyphae of 
Ozonium into the hyphae of Coprinus. However, I have reserved 
your specimen to study anew and compare it with the work of Penzig, 
which at this moment I do not have.” 
145 
