5. Diachaea thomasii Rex.
[Plate V.], Fig. 6, 6 a.
- 1892. Diachaea thomasii Rex, Proc. Phil. Acad., p. 329.
Sporangia gregarious, more or less crowded, purple and bronze, iridescent, globose sessile or short stipitate; stipe, when present, very short, thick, tapering rapidly upward, orange; hypothallus orange, prominent venulose, continuous; columella ochre yellow, rough, cylindric, tapering upward to one-half the height of the sporangium, obtuse; capillitium lax, of slender brown rigid threads, radiating from the columella in every direction, anastomosing to form a loose, large-meshed network; spore-mass brown; spores by transmitted light violaceous, minutely, unevenly warted, 10–12 µ.
The peculiar orange color of the calcareous deposits in stipe and columella easily distinguish this species. The capillitium is also distinctive, rigid, simple, and comparatively scant, lamprodermoid. Rex calls attention to the fact that under low magnification the spores appear spotted; but the spots are occasioned simply by the closer aggregation, at particular points, of the ordinary papillæ.
A southern species. All the specimens so far reported are from the mountains of North Carolina.
The specimens referred to under this name by Lister, Mon., p. 92, as coming from "Kittery, U. S. A." (Kittery, Maine?), are, no doubt, according to Mr. Lister's figures, Comatricha caespitosa Sturgis. See under that species.
C. LAMPRODERMACEÆ
Sporangia distinct, generally gregarious, more or less spherical; capillitium developed chiefly or solely from the summit of the columella.
Key to the Genera of the Lamprodermaceæ