Lichen parasemus Ach. Lich. Suec. 64. 1798.
Thallus usually continuous and smooth, but sometimes becoming thicker and roughened, granulate, chinky, or finally areolate, ash- to green-gray, and darkening, or even yellow-green, usually bordered wholly or in part by a black margin; apothecia small to large, 0.4 to 1.3 mm. in diameter, black, adnate to sessile, or rarely more or less immersed, flat with a prominent, concolorous, sometimes flexuous exciple, or sometimes becoming convex, with the exciple often covered ([Fig. 11]); hypothecium dark brown; hymenium pale below and pale brown above; paraphyses distinct ([Fig. 12]), but sometimes loosely coherent; asci clavate ([Fig. 13]), or rarely inflated clavate; spores oblong to ellipsoid, 10 to 18 mic. long and 5 to 9 mic. wide, rarely 3-celled ([Fig. 13]).
Collected in Fairfield, Lake, Adams, Highland, Hocking, and Butler counties. Also examined from Morgan, Madison, and Muskingum counties. On bark. Generally distributed in Ohio.
3. Buellia turgescentoides sp. nov.
Thallus a thick, continuous or scattered, flat or verrucose, areolate or subareolate, dull olive-brown, and darkening crust, covering small areas or spreading widely over the substratum, the marginal areoles sometimes lobulate; apothecia minute to small, 0.2 to 0.5 mm. in diameter, immersed to adnate, scattered or clustered, black, flat with the thin concolorous exciple visible, or convex with the exciple covered; hypothecium pale or darker brown; hymenium pale; paraphyses stout, distinct, but often loosely coherent; asci clavate or inflated-clavate; spores brown, 2-celled, oblong to oblong-ellipsoid, 8 to 13 mic. long, and 4 to 6 mic. wide, 8 in each ascus.
Collected in Lake County. On exposed igneous rocks. The type specimen is deposited in the writer's herbarium, and a cotype may be found in the State Herbarium.
This species is a coarser plant than Buellia turgescens (Nyl.) Tuck., with much stronger, darker thallus and apothecia on the whole larger.
Rhizocarpon Ram. in Lam. & DC. Fl. Fr. ed. 3. 2: 365. 1805.
Thallus usually verrucose, areolate or subareolate, tending toward squamulose conditions, better developed than in other members of the family, scarcely ever showing granulate conditions, and never disappearing entirely; apothecia also larger than in the other genera, adnate to immersed, usually black, but rarely white-pruinose; hypothecium usually dark brown; hymenium pale to light brown; spores 4-celled to muriform, and pale to brown, various conditions of septation and coloration sometimes appearing in the same hymenium.