DiDERMA 107 



brown or dark umber, with paler lines of dehiscence; sporangial 

 wail dehiscing irregularly or in a somewhat stellate manner, con- 

 sisting of two layers, the outer cartilaginous, brown on the outer 

 and white on the inner side, more or less adhering to the mem- 

 branous inner layer. Stalk short, black, furrowed, slender or 

 stout. Columella large, flat, discoidal, yellow to ochraceous 

 brown. Capillitium consisting of slender, simple or branched, 

 colorless threads. Spores purplish brown, spinulose, 10-14/x diam. 



Type locality: Tennessee. 



Habitat: On dead wood. 



Distribution: Colorado, *Maine, New Hampshire, New 

 York, North Carolina, Ontario, Pennsylvania, *Tennessee. 



Illustration: Lister, Mycetozoa ed. 3. pi. 94, figs. c. d. 



The flat, discoid sporangia on black stalks, similar in shape 

 to the sporangia of D. hemisphericum, distinguish the form from 

 D. radiatum, with which it is connected by intermediate forms 

 with more hemispherical sporangia and columellae, and usually 

 on red-brown stalks. 



18. Diderma asteroides Lister, Mycetozoa ed. 2. 113. 1911. 

 (N. Y. B. G. no. 12495, authentic material.) 



Chondrioderma asteroides A. & G. Lister, Jour. Bot. 40: 209. 1902. 



Licea antarctica (?) Speg. Bol. Acad. Cienc. Cordoba 11: 58. 1887. 



Diderma antarcticum {''antarctica'') Sturg. Mycologia 8: 37. 1916. (N, Y. 

 B. G. nos. 12486, 12487, type.) 



Plasmodium cream-yellow to bright orange (Lister). Spo- 

 rangia scattered or crowded, hemispherical or somewhat conical, 

 0.6 to 0.8 mm. high, sessile, rarely short-stalked or forming 

 plasmodiocarps, purplish brown, chocolate, or pinkish brown, 

 often mottled with darker spots or marked with numerous darker 

 lines radiating from near the apex to the base of the sporangium; 

 sporangial wall dehiscing by petaloid lobes, white on the inner 

 side, the outer layer brown, cartilaginous, with abundant deposits 

 of lime on the inner side, usually connected with the membranous 

 inner layer. Stalk very short, stout, white, often rising from a 

 white hypothallus. Columella ochraceous or cream-colored, 

 usually large, hemispherical, subglobose or depressed, but vari- 

 able and irregular, or small, rough or rugose. Capillitium of 

 slender, simple or anastomosing, colorless or purplish threads. 

 Spores purple-brown, minutely warted, 9-12 /x diam. 



Type locality: Italy. 



