Morgan, A.P. 1890. North American fungi: third paper. Journal of the Cincinnati Society of Natural History 12: 164.
Peridium depressed-globose, thickish, becoming firm and rigid, with a dense brown cortex of minute persistent scales and warts; the mouth small, circular, prominent, entire. Stipe long, slender, with a surface of brown lacerate scales, internally white, with a central pith of long loose fibers; the mycelial bulb large, irregularly depressed-globose. Threads of the capillitium long, slender, about as thick as the spores, hyaline, branched; spores irregularly globose, minutely warted, pale brown, 5-6 mic. in diameter.
Growing on the ground in rich soil in woods. Ohio, Morgan. Plant 2-4 inches in height, the peridium about 1/2 of an inch in diameter, the stipe nearly 1/4 of an inch thick; the mycelial bulb is sometimes larger than the peridium. It seems altogether different from T. exasperatum, Mont.
Etym.: The name refers to the verrucose nature of the exoperidium.
Spore-sac up to 10 mm diam, relatively small, of a peculiar shape, widely pyriform. Exoperidium verrucose, with appressed, semicaducous verrucae with a clayish aspect, dirty greyish brown to almost ferrugineous resembling when mature dried clay with crackings. Endoperidium reticulate and areolate from the scars of the endoperidial verrucae, lilac brown with ferrugineous hues. Mouth tubular, projecting, surrounded all along with persistent verrucae which, upon falling, leave a lighter clayish grey peristome. Socket with a conspicuous and large band, separated from the stem; this band appears to be formed by the exoperidium, since there is a second, inner, dentate one closely embracing the stem apex. Gleba light ferrugineous. Stem long, up to 60 x 4 mm, slender, scaly, reddish brown; later the sca es slough off and it becomes lighter and smooth, or with two or three long striae, ending basally in a conspicuous mycelial bulb, sometimes larger than the spore-sac.
Endoperidium formed by vesiculose cells loosely arranged in chains, 15-30 x 6-11 um. Spores under L.M. finally spiny to verrucose, 6.4-7.1 Âµm, almost hyaline to light yellowish; under SEM the ornamentation appears formed by "spines" which are conic or pyramidal, composed of several columns, some much anastomosed in high crests. Capillitium much septate, hyaline, branched; threads 2.5-11.0 Âµm diam, not swollen at the septa, brown.
Habitat: humiferous soil in forests, among litter and herbs. Distribution: North America: United States (Illinois, Indiana, Missouri, Ohio, Oregon). Africa: South Africa.
Lectotype: United States: Ohio, Cincinnatti, leg. A. P. Morgan, 1883, no 358 (BPI!) (Probably an isotype; isotype, S!).
Illustration: Morgan (op. cit.); Lloyd (1906: pl. 76, figs. 3-5); see also above.