1. Trichia fragilis, Sow. Sporangia obovoid to pyriform or clavate, often fasciculate, stipitate; the wall a thin membrane, with a thick dense outer layer of brown-red granules. Stipes long, erect or curved, simple or usually fasciculate and often connate, arising from a thin hypothallus. Mass of spores and capillitium from reddish-brown to yellow and ochraceous; elaters simple, rarely branched, 4–5 mic. thick, with very long tapering extremities, ending in smooth points 8–12 mic. long; spirals, three or four, perfectly smooth. Spores globose, minutely warted, 10–12 mic. in diameter.
Growing on old wood. Sporangia with the stipe 2–4 mm. in height, the sporangium .6-.8 mm. in diameter, the stipe usually longer than the sporangium. The color quite variable, mostly dull red-brown or blackish-brown, more rarely yellow or coffee-brown, usually opaque, rarely shining.
2. Trichia fallax, Pers. Sporangium obovoid to pyriform or turbinate, rarely clavate, stipitate; the wall thin, smooth and shining, colored as the spores and capillitium. Stipe more or less elongated, simple, erect, brownish below, filled with roundish vesicles. Mass of capillitium and spores yellowish, ochraceous or olivaceous; elaters simple or sometimes with several branches, 4–6 mic. thick in the middle, tapering gradually to each extremity, ending in smooth tapering points, 20–40 mic. in length; spirals, three, perfectly smooth. Spores globose, minutely warted, 10–12 mic. in diameter. [See Plate I, Fig. 22.]
Growing on old wood. Sporangium with the stipe 2–4 mm. in height, sporangium .6-.8 mm. in diameter, the stipe usually longer than the sporangium. Under high magnifying power the spores are seen to be minutely reticulated.
b. Elaters cylindric, ending in a smooth tapering point.
3. Trichia subfusca, Rex. Sporangium globose, rarely globose-turbinate, stipitate; the wall thickish, dull tawny-brown above, shading to dark brown at the base. Stipe simple, erect, brown or blackish in color. Mass of capillitium and spores bright yellow; elaters simple, rarely branched, cylindric, 3.5–4 mic. in thickness, ending in smooth tapering points, 10–12 mic. in length; spirals, four in number, perfectly smooth. Spores globose, minutely warted, 11.5–12.5 mic. in diameter.
On old wood and bark, Adirondack Mountains, New York. Dr. George A. Rex. Sporangium .5-.8 mm. in diameter, the stipe equal in height to the diameter of the sporangium.
4. Trichia erecta, Rex. Sporangium globose to globose-turbinate, stipitate; the wall of both sporangium and stipe with a rough outer layer of brown scales and granules, which, on the upper surface of the sporangium, soon breaks up into irregular patches. Stipes long, erect, usually simple, rarely fasciculate and connate. Mass of capillitium and spores, bright yellow; elaters simple, cylindric, 4 mic. in thickness, ending in smooth points, 4–6 mic. long; spirals four, often united by intervening branches, covered with numerous irregular spinules. Spores globose, minutely warted, 12–14 mic. in diameter.
Growing on old wood and bark, Adirondack Mountains, New York, Dr. Geo. A. Rex. Sporangium .5-.8 mm. in diameter, the stipe about 1 mm. in height. This Trichia is conspicuous by the checkering or areolation of the upper surface in the mature sporangia, affording a sharp contrast between the brown patches and the yellow bands.
§2. Chrysophidia. Sporangia globose, obovoid or somewhat irregular, sessile, rarely with a short stipe, usually closely crowded. Spores globose, the surface minutely warted.