338 PROCEEDINGS OF THE AMERICAN ACADEMY. 



Guttulina sessilis Van Tieghem. 

 Bull, de la Soc. Bot. de France, XXVII. p. 317. 1880. 



" Fruit sessile ; a simple droplet of pure white, resting directly on the 

 substratum. Spores oval, colorless, aggregated in a sphere and cemented, 

 as in the preceding species, by a gelatinous substance ; 4/x X 8fx. On the 

 integument of beans in a state of decay." France. 



Guttulina aurea and G. sessilis are known only from the original 

 descriptions above quoted. 



DICTY0STELIACE7E Rostafinski. 



Myxamoebos possessing slender elongated pseudopodia. Sori consist- 

 ing of spherical masses of spores or of a chain of spores ; stalked, the 

 stalks composed of distinct parenchyma-like cells with cellulose walls. 



ACRASIS Van Tieghem (1880). 



Spores concatenate, terminating an erect simple filament, consisting of 

 a single row of superposed cells. 



Acrasis granulata Van Tieghem. 

 Bull, de la Soc. Bot. de France, XXVII. p. 317. 1880. 



Spores spherical, with a slightly roughened or granular wall, having 

 a cuticularized external portion of deep violet color; 10/i-15/a in diam- 

 eter, often unequal in the same chain, the chain varying much in the 

 number of component spores and cells. 



On a culture of beer yeast. France. 



Known only from the original description. 



DICTYOSTELIUM Brefeld (1860). 

 Sori stalked ; the stalk simple or only occasionally bearing irregularly 

 disposed branches; luxuriant fructifications frequently gregarious. Sori 

 spherical, or subglobose. 



Dictyostelium mucoroides Brefeld. 



(Ceratopodium ehgans Sorokin.) 



Abh. d. Senck. Nat. Ges., VII. p. 85-108. PI. I-III. 1869. 



Sorus and stalk white, or when old, yellowish ; the fructifications 

 varvina: in height from 2-3 mm. to 1 cm. or more. Spores oval or 

 elongated ellipsoid, 2.4/x,-3jU X 4^-6ju. 



