- 1873. Dydymium melleum Berk. & Br., Jour. Linn. Soc., XIV., p. 83.
- 1873. Didymium chrysopeplum Berk. & C., Grev., II., p. 53.
- 1876. Physarum schumacheri Spr. var. melleum Rost., Mon., App., p. 7.
- 1892. Physarum melleum Massee, Mon., p. 278.
- 1896. Cytidium melleum (Berk. & Br.), Morg., Jour. Cin. Soc., p. 83.
- 1899. Physarum melleum (Berk. & Br.), Mass., Macbr., N. A. S., p. 47.
- 1911. Physarum melleum Mass., Lister, Mycetozoa, 2nd ed., p. 46.
Sporangia scattered, stipitate, globose, flattened below, clear yellow or honey colored; stipe short, about equaling the sporangium, pure white, somewhat wrinkled; columella small but distinct, white; hypothallus none, capillitium abundant, open, snow-white, with rather large angularly stellate nodes; spore-mass brown, almost black; spores by transmitted light, pale violet or lilac-tinted, almost smooth, 7.5–10 µ.
Easily distinguished by its white stipe, columella and capillitium in contrast with yellow peridial walls. N. A. F., 1395. Massee refers this number erroneously to P. schumacheri Rost. The description and specimen do not correspond. By that name the species has however, been hitherto known in the United States.
Eastern United States, common; rare west of the Mississippi.
Reported from Brazil, Japan and the tropic islands round the world. Portugal.
20. Physarum citrinum Schumacher.
- 1803. Physarum citrinum Schum., Enum. Pl. Saell., II., p. 201.
- 1911. Physarum citrinum Schum., List., Mycetozoa, 2nd ed., p. 51.
Sporangia gregarious, scattered, globose, somewhat flattened below, pale yellow, citrine, stipitate; the peridium thin, covered almost completely with small calcareous scales; stipe stout, erect, fragile, tapering upwards, furrowed, opaque, arising from a small hypothallus which is anon continuous from one sporangium to the next; columella small, conical, yellow; capillitium a rather dense, delicate network, the calcareous nodules yellow, numerous, roundish, and generally small; spore-mass black; spores under the lens violaceous, almost smooth, about 8 µ.
This species seems to be rare in the United States. It resembles somewhat P. melleum, from which it is distinguished by its yellow stipe. P. galbeum is a smaller form, and lacks the columella. Rostafinski strangely confused the synonymy here, including even P. rufipes Alb. & Schw.
New England, Ohio, Colorado.