Mitremyces. Nees.
Mitremyces is made up of two words: mitre, a cap; myces, a mushroom. It is a small genus, there being but three species found in this country. The spore-mass or gleba, in its young state, is surrounded by four layers. The outer layer is gelatinous and behaves itself somewhat differently in each species. This outer layer is known as the volva or volva-like peridium, which soon disappears. The next layer is called the exoperidium and is composed of two layers, the inner one quite thin and cartilaginous—in M. cinnabarinus it is a bright red; this is attached to a rather thick, gelatinous, outer layer which soon falls away, exposing the endoperidium, which is the layer seen in older specimens. Within the endoperidium are the spores, which are pale ochraceous or sulphur color, globose or elliptical in shape. They are contained in a separate membrane or sac; when they mature the sac contracts and forces the spores out into the air. The mycelium of this plant is especially peculiar, being composed of a bundle of root-like strands, translucent and jelly-like when young and fresh, but becoming tough and hard. This genus is called by some authors Calostoma, meaning a beautiful mouth, a very appropriate name, as the mouths of all American species are red and quite beautiful.
Mitremyces cinnabarinus. Desv.
Figure 481.—Mitremyces cinnabarinus. Natural size.
The rooting strands are long, compact, dark when dry. Exporidium bright red, smooth internally; the outer layer thick, gelatinous when fresh, finally breaking into areas and curling inward. The separation is caused by the fact that the cells of the thick gelatinous portion expand by the absorption of water, while those of the inner layer do not, hence the rupture occurs. The endoperidium and rayed mouth are bright red when fresh, partially fading in old specimens.
The spores are elliptical-oblong, punctate-sculptured, varying much as to size in specimens from different localities; 6–8×10–14 in West Virginia specimens. Massachusetts specimens, 6–8×12–20. Lloyd.
I have seen these specimens growing in the mountains in West Virginia. They quickly arrest the attention because of their bright red caps. They seem not, as yet, to have crossed the Alleghenies—at least I have not found it in Ohio. It has a number of synonyms: Scleroderma calostoma, Calostoma cinnabarinum, Lycoperdon heterogeneum, L. calostoma.
The plants in Figure 481 were photographed by Dr. Kellerman. Mr. Geo. E. Morris of Waltham, Mass., sent me some specimens early in August, 1907.