The Myxomycetes of the Miami Valley, Ohio. 



29 



27. Physarum SKRPUivA Morgan, n. nom. Plasmodiocarp 

 roundish or oblong to much elongated, bent, annular and 

 flexuous, sometimes by confluence branched and reticulate ; 

 the wall a firm yellowish membrane, with a thin, rough, 

 closely adherent coat of granules of lime, dull ochre to lemon- 

 yellow and orange in color. Capillitium a dense net-work of 

 tubules, for the most part filled with lime, only here and there 

 short, slender, empty spaces; the nodules large, numerous, 

 white or yellow, angular and with pointed lobes and branch- 

 lets. Spores globose, minutely warted, dark violaceous, 9-1 1 

 mic. in diameter. 



Growing on leaves, bark, lichens, etc. Plasmodiocarp .3~.4 

 mm. in thickness and of varying length. This species is in 

 the herbarium of Schweinitz, at Philadelphia, with the name 

 Physarum reticulatum ; it is described by George Massee as 

 Physarum gyrosum ; by Lister it is incorporated with several 

 other species under Badhamia decipieiis. 



28. Physarum contkxtum Pers. Sporangia sessile and 

 closely crowded together, roundish or more or less elongated, 

 flexuous and complicate, the apex plane or impressed ; the 

 wall a firm yellowish membrane, covered by a thick pulvera- 

 ceous layer of lime, white, ochraceous or yellow, easily 

 crumbling and breaking up. Capillitium a loose net-work of 

 tubules, much expanded at the angles; the nodules of lime 

 very large, white or yellow, numerous, angular, and irregular, 

 by confluence lobed and branched, sometimes massed together 

 in the center of the sporangium. Spores globose, minutely 

 warted, dark violaceous, 10-13 mic. in diameter. 



Growing on bark, leaves, mosses, etc. Sporangia with a 

 width of .3-. 5 mm. and varying in length from .5 mm. to 1 or 

 2 mm. The sporangia are often so much crowded as to appear 

 to be grown together. Diderma ochroleucum B. & C. belongs 

 to this species. Physarum conglomeratum Fr. is a closely 

 related species, with smaller and smoother spores. I have 

 not met with this. 



29. Physarum diderma Rost. Sporangia large, irregu- 

 larly globose or oblong, sessile, but without a hypothallus, 

 closely crowded together and sometimes confluent. The wall 

 composed of two distinct and separate layers ; the outer a 



29 



