210—MYCENASTRUM. 
. The genus .is characterized by the spiny capillitium (see plate 
5, fig. 8). Even in very immature plants these peculiar threads can 
be distinguished. We have never seen them so excessively spiny as 
shown by the figure in Engler and Prantl. Morgan’s drawing does 
not well represent them. 
Many species of Mycenastrum have been described which Dr. 
Hollos claims to be all forms of the same plant, and that it is cosmo¬ 
politan. These are mostly included in Saccardo as Sclerodermas, but 
the genus is widely different from Scleroderma. The original species 
came from France and was called Eycoperdon Corium. In this country 
the .species is usually known as Mycenastrum spinulosum, but I do 
not think it presents any characters by which it can be distinguished 
from the European plant. (Our previous note on the subject, Myc. 
Notes, p. 79, to the contrary notwithstanding). 
211—MYCENASTRUM CORIUM. 
(Plate 5.) 
If we accept Hollos’ references of all species of Mycenastrum to 
this one species, the plant grows in every continent in the world. In 
the United States, its home is the plains of the Western States, and it 
occurs in abundance in Colorado, Kansas, Iowa, as far south as Texas, 
west to the coast (Southern California), Washington, The furthest 
east that we have specimens is near Chicago. 
As found in this country the plant is usually globose or de¬ 
pressed globose, but specimens from Texas (plate 5, figures 4 and 5) and 
from Hungary (plate 5, fig. 6) are obovate in shape. The peridium is 
thick, hard, almost woody. It varies in thickness from one to four 
millimeters. When young the cortex is smooth, or with a felty ap¬ 
pearance (see plate 5, fig. 2). It dries up and disappears when the 
' plant ripens, leaving the peridium smooth. The plant dehisces by the 
peridium splitting into a number of stellate lobes, but usually the plant 
breaks away from its base, and is rolled about unopened for months. 
In ripening the gleba first turns bright olive (almost yellow). Finally 
it becomes dark purplish brown. The peculiar capillitium threads are 
the generic character. They are simple, or few branched, short, thick, 
pointed at the ends, and bearing little spiny prickles. The spores are glo¬ 
bose, large, 8-10 me., warted. (*) 
In Myc. Notes, p. 79, we drew attention to the fact that the 
American plant has columella strands (see plate 5, fig. 3). In no 
other country has a columella ever been noted in a Mycenastrum. If 
it were a constant character of our plant we should say it was 
of specific importance, but an examination of many specimens shows 
that while present in some specimens, in others there is no trace of it 
and there is no other difference between them. It is simply a fact 
that some plants possess columellse and others do not. This columella 
is of the nature of undeliquescing gleba, though the hyphae while of a 
(*) Morgan states they “often have a minute or slender hyaline pedicel ” We have never 
seen them, though an examination of immature gleba demonstrates they are borne onthebasidia 
on short pedicels. 
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