THE SLIME MOLDS OF OHIO 
15 
12. P. polycephalum Schwein. Sporangia confluent in clusters of from 
five to many, gray or yellowish, stalked, the stalks of the cluster combined; 
the entire cluster often having the appearance of a mass of rope upon a post. 
Sporangium wall membranous with scattered clusters of lime granules. 
Capillitium of yellow lime knots connected by a network of threads. Spores 
violet brown, minutely roughened, 9 to lOmmm. in diam. 
Common on logs, sticks, leaves, etc. 
13. P. nucleatum Rex. Sporangia gregarious, globose, 0.5mm. in diam., 
white, stalked. Sporangium wall membranous containing clusters of white 
lime granules. Stalk 1mm. long, yellow, rugose. Columella none. 
Capillitium of small white lime knots connected by a network of colorless 
threads, having usually a white ball of lime at the center. Spores violet 
brown, minutely spinulose, 6 to 7mmm. in diam. 
Summit Co., Jefferson Co., (Licking Co.—Oberlin College Herb.) 
14. P. didermoides (Acharius) Rost. Sporangia crowded, ovoid, about 
0.5mm. in diam., white, stalked or sessile. Outer sporangium wall 
densely charged with white lime granules, early deciduous, leaving the 
sporangia dark gray in color. Stalk white, membranous, variable in size, 
often flattened. Hypothallus white. Capillitium of numerous rounded 
white lime knots connected by short hyaline threads. Spores dark violet, 
spinulose, 10 to 13mmm. in diam. 
(Miami Valley—Morgan), (Ohio—Macbride), (Ohio—Lister.) 
15. P. compressum Alb. & Schw. Sporangia gregarious, subglobose, 
or reniform, compressed, splitting along the ridge, white or gray, stalked 
or sessile, roughened. Sporangium wall membranous containing dense 
clusters of white lime granules. Stalks stout, furrowed. Columella absent. 
Capillitium of numerous white lime knots connected by hyaline threads. 
Spores dark brown, spinulose, 9 to 14mmm. in diam. 
(Miami Valley—Morgan), (Ohio—Macbride). 
16. P. leucopus Link. Sporangia gregarious, globose, 0.5mm. in 
diam., white, stalked. Sporangium wall membranous, containing white 
lime granules. Stalk white, stout, larger at base, short, brittle. Columella 
absent. Capillitium of large irregular white lime knots connected by 
hyaline threads. Spores violet brown, spinulose, 8 to lOmmm. in diam. 
Not rare in Ohio. 
17. P. globuliferum (Bull.) Pers. Sporangia gregarious, globose, 
0.5mm. in diam., white, stalked, erect. Sporangium wall membranous 
containing lime granules. Stalk white, sometimes dark below, about 1mm. 
long. Columella present, conical. Capillitium of white rounded lime 
knots connected by a network of hyaline threads, persistent and retaining 
the form of the sporangia after spore disperal. Spores violet brown, 
minutely roughened, 6 to 8mmm. in diam. 
Common. 
