304 A Monograph of the Myxogastres. 



Physarum diderma, Rost. 



Sporangia sessile, adnate by a narrow base, globose, snoio-white, 

 wall do'uUe, outer dense, fragile, thick, charged with lime, inner 

 thin, scjmrafed for some distance from the outer, the obsolete 

 columella composed of numerous angularly-globose granules of 

 lime; spores dingy violet, spinulose, 9 — 10 ^i diameter. 



Physarum Diderma, Rost., Mon., p. 110 ; Sacc, Syll., vii., 9, 

 n. 1168. 



Poland. 



The above imperfect description suggests the genus Chon- 

 drioderma rather than Physarum. 



Physarum lividum, Rost. 



Sporangia crowded, sessile, subglobose or irregular, blackish, 

 thickly covered with small white 2}cirticles of lime; columella 

 absent ; spores globose or subangular, opaque, minutely aspcru- 

 lose, 10 — 12 II diameter; capillitium almost absent. 



Physarum lividum, Rost., Mon., p. 95; Sacc, Syll., vii., 1, 

 1169. 



On fallen Opuntia. Sweden ; Germany ; Algeria ; N. 

 America. 



I have no knowledge of the present species, which appears 

 to be too briefly described to insure future identification. 



(Rostafinski's Synonyms.) 

 Physarum griscum, Link, Diss. II., f. 42 (1809). 

 Physarum effusum, Link, Herb. (1809). 

 Physanvm conglobatum, Fr., Sym. Gast., p. 21, p.p. non Dit. 



(1818). 

 S])umaria lichcniformis, Sz., Amcr. Fung., n. 2364 (18.34). 

 Didymium jyhysaroidcs, M. Fl. Alg., p. 412, non Fr. (1846). 

 Zicea alba, Boug., Herb. (1846). 



Physarum conglomeratum, Mass. (figs. 210—212, 284 — 286). 

 Sporangia sessile on a broad base, convex above, crowded, 

 subangular from mutual pressure, wall double, outer containing 



