154 Ciiicijinati Society of Natural History. 



Growing on sticks, leaves, herbaceous stems, etc. Sporan- 

 gium .8-1.2 mm. in diameter, the stipe shorter than the 

 diameter, sometimes very sliort or quite obsolete. 



8. DiDERM.v tp:st.\ceum, Schr. Sporangia circular or oval, 

 much depressed, sessile, without an}- hypothallus, gregarious 

 irregularly scattered, sometimes close and even confluent. 

 The outer calcareous layer of the wall thick, smooth, crusta- 

 ceous, separate and distinct from the inner membrane, white 

 or pinkish-white to rose-red in color, gradually breaking up 

 in pieces and falling away ; the inner membrane thin, pellu- 

 cid, cinereous from the adherent granules of lime, irregularly 

 dehiscent from the apex downward. Columella hemispheric 

 or depressed, granulose roughened, white, pinkish, or fle.shy- 

 red. Capillitium of very slender, nearly colorless threads, 

 more or less branched. Spores globose, very minutely 

 warted, 8-io mic. in diameter. 



Growing on old leaves, wood, mosses, etc. \'ery common 

 in this country. vSporangium .6-r.o mm. in diameter, some- 

 times a little irregular, especially the form growing on 

 mosses, and occasionally confluent. 



9. DiDERMA ciNEREUM, Morgan, n. sp. Sporangia subglo- 

 bose, more or less irregular, somewhat depressed, sessile, usu- 

 ally close or crowded, sometimes confluent ; the hypothallus a 

 thin membrane, pellucid or with occasional patches of lime 

 granules, sometimes not apparent. The wall very thin, even 

 or rugulose, cinereous, the thin membrane covered by a single 

 layer of closely-adherent granules of lime, rupturing irregu- 

 larly. Columella white, hemispheric or depressed and irreg- 

 ular, the surface granulose. Capillitium of very slender, 

 colored threads, the extremities pellucid, more or less branched. 

 Spores globose, minutely warted, violaceous, 9-1 1 mic. in 

 diameter. Plate XII, Fig. 46. 



Growing on old wood, leaves, etc. The sporangium .3-. 5 

 mm. in diameter, thin and smooth or rugulose. The species 

 superficially greatly resembles Physarum ciuo chvi. 



10. DiDERMA DiFFORME, Pers. Plasmodiocarp roundi.'^h, 

 oblong, or more or less elongated and flexuous, scattered or 

 seriatcly disposed; the hyjiothallus a thin brownish mem- 

 brane, or commonly not apparent. The outer calcareous 



