A plasmodiform gathering of this species which will be mistaken for an entirely different thing, is yellow, sessile, and has adherent spores; looks like a badhamia, but is after all a leocarpus and probably belongs here. The spores are irregularly clustered and the badhamioid section of the capillitium seems now dominant.
California.
B. DIDYMIACEÆ
Key to the Genera of the Didymiaceæ
| 1. Fructification æthalioid | 1. Mucilago | |
| 2. Fructification plasmodiocarpous, or forming more often distinct sporangia. | ||
| a. Calcareous deposits crystalline, stellate | 2. Didymium | |
| b. Calcareous deposits amorphous, peridium double | 3. Diderma | |
| c. Calcareous deposits in form of scattered scales | 4. Lepidoderma | |
| d. Peridium double, the outer gelatinous | 5. Colloderma | |
1. Mucilago (Mich.) Adans.
- 1729. Mucilago Micheli, Nov. Pl. Gen., in part.
- 1763. Mucilago (Mich.) Adanson, Fam. des Pl., II., p. 7.
- 1791. Spumaria Pers. in Gmelin, Syst. Nat., II., p. 1466.
Fructification æthalioid, consisting generally of large cushion-shaped masses covered without by a white foam-like crust; within, composed of numerous tubular sporangia, developed from a common hypothallus, irregularly branched, contorted and more or less confluent; the peridial wall thin, delicate, frosted with stellate lime-crystals, which mark in section the boundaries of the several sporangia; capillitium of delicate threads, generally only slightly branched, terminating in the sporangial wall, marked with occasional swellings or thickenings.
By the descriptions offered by most authors, and especially by Rostafinski's figures (Mon., Pl. ix.), a pronounced columella is called for in the structure of Spumaria. The individual sporangia rise from a common hypothallus, and occasionally portions of this run up and give to a sporangium the appearance of being stipitate. Sometimes also this upper extension of the hypothalline protoplasm passes beyond or behind the base of the sporangium or between two or more, and is more or less embraced by these in their confluent flexures. This, it seems, suggested Rostafinski's elaborate diagram, Fig. 158; at least, none other form of columella is shown by American materials at hand.
1. Mucilago spongiosa (Leyss.) Morgan.