4. Lycogala conicum Pers.
- 1801. Lycogala conica Pers., Syn. Fung., p. 159.
- 1875. Dermodium conicum (Pers.) Rost., Mon., p. 284.
Æthalia scattered, sometimes two or three together, small 2–4 mm. high, conical, sessile, pallid, grayish brown, marked by obscure black reticulations, opening regularly at the somewhat acuminate tip; peridium thin in structure, as in L. epidendrum, but more delicate; capillitium made up of abundant, slender, uniform threads almost smooth, simple, the free ends obtuse, taking origin in the cortex much as in the preceding species; spores in mass ochraceous, by transmitted light colorless, minutely warted or faintly reticulate, about 5 µ.
A very distinct and rare little species. Well described by Persoon, who also appears to have observed the plasmodium "primo rubra." The color of the mature form varies with age; at first somewhat purplish. Dr. Rex collected it in Pennsylvania; Mr. Morgan has it from Ohio; our specimens are from southeastern Missouri.
Order V
TRICHIALES
Fructification sporangial, rarely plasmodiocarpous, the sporangia stalked or sessile, gregarious or closely crowded, limeless throughout; the capillitium of definite threads, free or attached to the sporangial wall, isolated or combined into a net; spores generally some shade of yellow, never purple or black.
The distinguishing feature in this order is found in the peculiar sculpture of the capillitial threads. This is suggested by the tubules of Lycogala, though probably the resemblance is superficial only. The individual threads, as in Trichia, are called elaters, from their probable efficiency in spore-dispersal.
As here limited, the order is coextensive with the Calonemeae of Rostafinski, except that that includes in addition the genera Prototrichia and Dianema. The course of differentiation may be assumed to start with Dianema, through the Perichaenaceae to the Arcyriaceae and again from the same starting-point through Prototrichia to the Trichiaceae.
Key to the Families of the Trichiales