The separation of the exoperidium is effected by the cartilaginous 
layer breaking into areas and curling in. The separation is caused, in 
my opinion, by the fact that the cells of the thick gelatinous portion 
swell and expand by the absorption of water, while those of the inner 
layer do not, hence rupture occurs. At first it causes a “buckling” 
of the layer shown in plate 8, fig. 2. Next, the layer is torn by the 
swelling of the outer gelatinous portion without a corresponding 
expansion of the inner (see plate 8, fig. 3). Finally the pieces curl 
inward and fall off. Frequently we find a mass of these gelatinous 
fragments of the exoperidium on the ground encircling a plant. They 
appear like a cluster of “fish eggs,” only the nuclei are red, instead 
of black.* 
THE GENERIC NAME. 
Nees von Fsenbeck illustrated and called this plant Mitremyces 
in 1816. For over seventy years his name was accepted and used, 
practically by all mycologists the world over. A monographer wishing 
to make a change and attach his name to nine of the ten species he 
considers, digs up from an obscure French journal a doubtful name 
(Calostoma), known but rejected by such men as Fries and Schweinitz, 
and attempts to change the accepted usage of seventy years. Others 
may follow if they wish, but not I. 
The genus Husseya of Berkeley, as clearly shown by Massee, is 
not different. 
THE MOUTHS OF MITREMYCES. 
Among the Gastromycetes, the mouths of all species of Mitre¬ 
myces, as far as we know, are peculiar to this genus. They are raised, 
rayed, and open by longitudinal slits along the rays. In addition, 
whatever may be the color of the peridium, the mouths of all the 
American species are red. A good idea of their appearance can be 
obtained from our plates, also from Morgan’s figures. They are very 
poorly and inaccurately shown in Massee’s plates. 
THE SPORES. 
No other genus has, to my knowledge, spores colored like 
Mitremyces. They are pale ochraceous, or sulphur color. In shape 
they are either globose or elliptical. There are no capillitia, but 
usually remains of hyphse tissue are observed mixed with the spores, 
(shown in plate 9, fig. 6). In this respect alone the genus approxi¬ 
mates Scleroderma. 
THE SPORE SAC. 
The spores are contained in a separate membrane or sac, at first 
lining the endoperidium. As the plant matures this spore-sac con¬ 
tracts, forcing the spores through the slits of the rayed mouth. So 
*Massee states “the structure is in evep r respect homologonous with the peridium in the 
Phalloideae, but differs in being entirely deliquescent at an early period ; hence no trace of its 
presence is to be seen in mature specimens.” The exoperidium no more separates by deliques¬ 
cence than does the cortex of a Bovista. It is a mechanical action of absorption of water by a 
gelatinous substance, but it does not deliquesce, and the use of this word in connection with the 
phenomenon is misleading. 
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