Craterium 87 



pale brown, or brown; lid convex and above the rim of the 

 sporangium, or flat and below it, white or concolorous; sporangial 

 wall of two layers, the outer cartilaginous, thickened at the rim 

 below the lid, translucent below and continued into the translu- 

 cent stalk, the inner layer more or less charged with lime-granules. 

 Stalk cylindrical, plicate, 0.3 to 0.5 mm. long, yellowish, pale 

 brown, or dark brown, rising from a circular hypothallus. Capil- 

 litium of slender, colorless threads, connecting numerous, large, 

 white lime-knots, often combined in the center to form a pseudo- 

 columella. Spores violet-brown, minutely warted, 8-9 /u diam. 

 (Plate 9, fig. 1.) 



Type locality: Germany. 



Habitat: On dead leaves. 



Distribution: Common in the United States and Canada. 



Illustration: Lister, Mycetozoa ed. 3. pi. 78. 



This species is said to have yellow threads and yellow lime- 

 knots in the capillitium at times, but I have never seen them in 

 American specimens. Two distinct phases occur; the small, dark 

 one with lids below the rims; and the larger, paler form with 

 convex lids extending above the rims; the latter is not uncommon, 

 but the former is more abundant. Another phase with long, dark, 

 cylindrical sporangia, and convex lids, is occasionally found. A 

 collection from Pike County, Pennsylvania, consists of minute 

 goblet-shaped sporangia, 0.2 to 0.3 mm. in height over all. 



2. Craterium concinnum Rex, Proc. Acad. Nat. Sc. Phila. 1893; 

 370. 1893. 



Plasmodium at first milky, then cream-colored (Lister) . Total 

 height 0.5 to 0.7 mm. Sporangia broadly funnel-shaped or goblet- 

 shaped, 0.2 to 0.5 mm. diam., stalked, smooth, pale or dark brown, 

 often paler above, opening by a well-defined, paler, convex lid; 

 sporangial wall cartilaginous. Stalk red-brown, 0.2 to 0.3 mm. 

 high. Capillitium consisting of numerous small, angular, brown- 

 ish lime-knots, connected by short, hyaline threads, sometimes 

 with a small pseudo-columella. Spores purplish brown, minutely 

 warted, 8-9 y. diam. 



Type locality: Philadelphia, Pennsylvania. 



Habitat: On decaying chestnut burs of the preceding year. 



Distribution: Connecticut, Massachusetts, New York, 

 *Ohio, Pennsylvania, Virginia. 



