184 Mycetozoa of North America 



threads, sometimes divided or lobed towards the surface of the 

 aethahum to show the contours of the component sporangia. 

 Spores black in mass, purplish gray by transmitted light, with a 

 pale area of dehiscence, closely and minutely spinulose, 11-15 n 

 diam. 



Type locality: Sweden. 



Habitat: On dead coniferous wood. 



Distribution: California, Massachusetts, *Oregon, *Penn- 

 sylvania, Washington. 



Illustration: Lister, Mycetozoa ed. 3. pi. 217, figs. a-c. 



Macbride {loc. cit.) considers the form as agreeing with the 

 description of Stemonitis Tuhulina Alb. & Schw. (Consp. Fung. 

 102. 1805), but apparently the type, if still existent, has not 

 been compared. Albertini and Schweinitz described the spore- 

 mass color of S. Tuhulina as brown, which would indicate a con- 

 fluent phase of some species of Stemonitis. In view of the known 

 errors and failings of the earlier students, it seems better to accept, 

 at least for the present, the name of the form of Fries, which is 

 generally accepted as representative. A. crihrosa is practically 

 like A. fuliginosa in appearance and spores, but differs materially 

 in the capillitium, which is an elastic network above the ragged 

 columellae, instead of branching strands. So far as I know only 

 five developments have been found in North America, the last by 

 Miss E. E. Morse in Mt. Lassen National Park, California, in 

 August 1928. Earlier gatherings were by Dr. A. P. D. Piguet, 

 at Sharon, Massachusetts, in May 1910; Mr. Hugo Bilgram, at 

 Lafayette, Pennsylvania, in May 1911; Prof. T. H. Macbride, on 

 Mt. Ranier, Washington, in 1913; and it was reported by Peck 

 and Gilbert from Oregon in August. 



Genus 25. BREFELDIA Rostafinski, Versuch 8. 1873. 



Aethalium pulvinate, consisting of subcylindrical, somewhat 

 branched and confluent sporangia, rising from a base of spongy, 

 barren tissue, which is continued among the lower portions of the 

 sporangia in irregular folds; imperfect sporangial walls and cen- 

 tral columellae sometimes present. Capillitium of numerous 

 horizontal threads, uniting at the surface of the adjacent sporan- 

 gia to form vesicles with many chambers. 



A single species. 



