Diderma hemisphaericum

Diderma hemisphaericum (Bull.) Hornem. Fl
Dan. 33: 13. 1829.
Reticularia hemisphaerica Bull. Hist. Champ. Er. 93. 1791.
Physarum depressum Schum. Enum. PI. Saell. 2: 202. 1803.
Reticularia contorta Poir. in Lam. Encyc. 6: 182. 1804.
Didymium hemisphaericum Pries, Syst. Myc. 3: 115. 1829.
Didymium Michelii Libert, PL Crypt. 180. 1832.
Physarum Michelii Corda, Ic. Fung. 5: 57. 1842.
Chondrioderma Michelii Rost.; Euckel, Jahrb. Nass. Ver. Nat. 27-28: 74. 1873.
Diderma Michelii Morgan, Jour. Cine. Soc. Nat. Hist. 16: 153. 1894.
Chondrioderma hemisphaericum Torrend, Broteria 7: 103. 1908.
Sporangia gregarious, discoid, 0.6-1.2 mm. in diameter, depressed above and of ten umbilicate below, stipitate or sometimes sessile; peridium double, the outer layer white, fragile, crustaceous, soon breaking at the margins, closely applied to the delicate, cinereous inner layer, which ruptures irregularly; stalk up to 1 mm. tall, rather stout, calcareous, white or pallid to alutaceous or brownish, longitudinally furrowed, the furrows continued as veins on the lower surface of the sporangium, rarely lacking; capillitium delicate, the threads colorless or pale violet-brown, sparsely branched, often scanty; spores pale violaceous-brown by transmitted light, nearly smooth, 8-9.5 p in diameter; Plasmodium opaquewhite.
Type locality: France.
Habitat: On leaves and other plant litter, occasionally on wood. Distribution: Throughout North America; cosmopolitan.