STEMONITIS 167 



8-10 mm. tall but occasionally varying from 5-15 mm.; stem jet- 

 black, shining, usually expanded at base into a broad disk with con- 

 spicuous rhizoidal outgrowths; columella dark, tapering upward, and 

 becoming dissipated just below tip; capillitium open, peridial net 

 pale, with many large, irregular meshes 50-125 fx wide; hypothallus 

 continuous, well developed, thin, transparent, or thicker and then 

 silvery; spores bone-brown * in mass, yellowish brown or lilaceous 

 brown by transmitted light, minutely verruculose, 8-9 /j, in diameter. 



The capillitium often possesses numerous membranous expansions 

 near the stipe, as in the type. Distinguished from 5. splendens by the 

 smaller size, erect habit, pale large-meshed surface net, more ferrugi- 

 nous cast. European authors generally regard this as merely a form of 

 S. splendens with large irregular meshes. Brandza (1929) reports it as 

 exceeding 5 cm. in height. 



On dead wood, temperate North America, chiefly west of the 

 Mississippi, Cuba. Also reported from Europe, south and west Africa, 

 Manchuria and Japan. 



12. Stemonitis axifera (Bull.) Macbr. 



N. A. Slime-Moulds ed. 2. 168. 1922. 

 PI. XI, Figs. 266, 267. 



1791. Trichia axifera Bull., Champ. 118. pi. 477, fig. 1. 

 1818. Stemonitis ferruginea Ehr., Sylv. Myc. Berol. 25. 

 1829. Stemonitis ferruginea Ehr. ex Fr., Syst. Myc. 3 : 158, in part. 

 1894. Stemonitis microspore, List., in Morgan, Jour. Cin. Soc. Nat. Hist. 

 16 : 138. 



Sporangia cylindrical with acuminate apex, fasciculate in small, 

 dense clusters, wood-brown* to avellaneous *, 7-15 mm. tall; stem 

 black, shining, }i to % total height; columella branching evenly, 

 dissipated before reaching the tip, branches clear brown, dividing and 

 anastomosing and at the surface uniting to form a fine-meshed peridial 

 net; hypothallus membranous, common to a cluster; spores pallid, 

 faintly ferruginous, spherical or somewhat oval or irregular, nearly 

 smooth, or, under oil immersion, faintly roughened or spinulose, 5-7 /x. 

 Plasmodium white. 



This is S. ferruginea Ehr., under which name both it and S . jlavogenita 

 Jahn are commonly distributed. Bulliard's reference to the white 

 color of the early stages would seem to be distinctive. Fries includes 

 both Bulliard's small-spored form with white plasmodium and a 

 larger-spored form with yellow plasmodium under Ehrenberg's name. 



Distribution world-wide; common. 



