144 Natural History Bulletin. 



This is perhaps the most showy species of the list. The 

 brilliantly iridescent sporangia are lifted above the substratum 

 on snow-white columnar stalks; these are again joined one to 

 another by the pure white vein-like cords of the reticulate 

 hypothallus. The plasmodium may spread very widely over 

 all sorts of objects that come in the way, dry forest leaves 

 and sticks, or the fruit and foliage of living plants, I am 

 indebted for specimens to Mr. Holway, of Decorah, who 

 reports that the plasmodium seemed to over-run " a whole 

 hillside." The very closely related and likewise exceedingly 

 beautiful species, D. lencopoda^ Bulliard, is to be looked for 

 here as it has been found east of the Mississippi river. It 

 differs from the present form only in having cylindric instead 

 of globose sporangia. The stipe in our specimens is much 

 broader than the cylindrical columella. July — August. 



SPU MARIA, Persoon. 



Sporangia united to form sethalia, more or less branching, 

 covered with a foam-like calcareous cortex. Columella like- 

 wise branching, the capillitium passing from the columella to 

 the sporangium walls and forming an intricate net. 



A single species only, and that limited to Europe and North 

 America. 



42. Spumaria alba, Bulliard. Plate VII, Figs. 6, 6a and 6h. 



Plasmodium white; fruit-masses ashen or gray, one to two 

 centimeters wide, two or three long, very fragile and porous. 

 Columella hollow, not attaining the end of the sporangium. 

 Capillitium-net more or less thickened at the points of inter- 

 section. Spores violet-black, very rough, .012-.014. 



Not rare in July and August on various parts of living 

 plants. The white frothy plasmodium creeps from its nutri- 

 tive base up blades of grass or stems of herbaceous plants, 

 sometimes for the distance of a foot or more, and is scarce 



