PHYSARUM 75 



ocarpous, calcareous, white or ashen; peridium thin, covered with 

 squamules, opening irregularly, usually by apical cleft; stipe, when 

 present, short, stout, more or less sulcate, dark brown or ashen; 

 capillitium a rather loose net, the nodules white, variable in size and 

 shape; spores purplish brown, warted, the warts sometimes irregularly 

 grouped, about 10-12.5 jx. Plasmodium grayish white. 



Rather rare in North America. Known from Pennsylvania, Iowa, 

 Colorado, California, Oregon, Washington, also Puerto Rico, Bolivia, 

 Argentina. Cosmopolitan. 



48. Physarum straminipes List. 



Jour. Bot. 36 : 163. 1898. 



Sporangia grayish white, obovoid or wedge-shaped, 0.7 mm. in 

 diameter, clustered or scattered, stipitate or sessile, when stipitate 

 stalks long, weak; peridium membranous, pale purple; capillitium a 

 persistent rigid net, the nodules white, rounded, sometimes aggregate 

 as a pseudocolumella; spores purple-brown, 10-11 fx, warted, the 

 papillae in definite patches. Plasmodium white. 



Related to P. compressum. 



Oregon, Chile; Europe, New Zealand. 



49. Physarum newtoni Macbr. 



Bull Nat. Hist. S. U. Iowa 2 : 390. 1893. 



Sporangia simple, gregarious, short-stipitate or sessile, globose or 

 flattened, and then depressed and deeply umbilicate above, purple, 

 smooth, thin-walled; stipe when present very short and concolorous; 

 columella none; hypothallus none; capillitium abundant, delicate, with 

 more or less well developed nodules, which are also concolorous; spores 

 by transmitted light dark brown, thick-walled, rough, nucleated, 

 about 10 /x. Plasmodium dark violet. 



A very handsome little species collected by Professor G. W. Newton 

 in Colorado, at an altitude of several thousand feet. Easily recognized 

 by its almost sessile, rose-purple, generally umbilicate sporangia. 



Colorado; Japan. 



50. Physarum roseum Berk. & Br. 



Jour. Linn. Soc. 14 : 84. 1873. 



Sporangia gregarious, globose, 0.4 mm. in diameter, rose-red, stip- 

 itate; sporangium wall membranous with innate clusters of purple- 

 red lime granules; stalk erect, slender, brown, rugulose, translucent; 



