146 Mycetozoa of North America 



Illustration: Macbr, & Martin, Myxomycetes pi. 11, figs. 

 251, 252. 



The banded character of the spores sharply defines this species 

 from the two preceding ones. The bands form a net on the 

 spores which is usually complete, although the number of meshes 

 varies. The surface-net of the capillitium is usually present only 

 in the lower half or three-quarters of the sporangium and may be 

 absent entirely. Comatricha reticulata Gilb., from Oregon, is 

 apparently a form of 5. virginiensis without surface net, and 

 deserves no specific recognition. 



4. Stemonitis trechispora (Torrend) Macbr. N. A. Slime-Moulds 

 ed. 2. 159. 1922. 



Stemonitis trechispora Berk., not published. (N. Y. B. G. nos. 6184, 11971, 



type material.) 

 Stemonitis fusca Roth var. trechispora Torrend, Fl. Myx. 14L 1909; Lister, 



Mycetozoa ed. 2. 144. 1911; Currie, Trans. Roy. Can. Inst. 12: 296. 



1920. 

 Stemonitis trechispora (Berk.) Torrend; Jahn, Ber. Deutsch. Bot. Ges. 41: 394. 



1924. 

 Amaurochaete trechispora Macbr. & Martin; Martin, Jour. Wash. Acad. Sc. 



22: 89. 1932. (N. Y. B. G. no. 6897, type material); Hagelstein, Myco- 



logia 34: 250. 1942. 

 Stemonitis trechispora Macbr.; Macbr. & Martin, Myxomycetes 160. 1934; 



Hagelstein, Mycologia 28: 615. 1936. 



Plasmodium milk-white. Developments 10 to 15 cm. across, 

 dividing into many small clusters of closely combined sporangia. 

 Total height 3 to 7 mm. Sporangia cylindrical, dull black, 

 stalked, sometimes free and distinct, more often confluent near 

 the base, and occasionally confluent throughout or nearly so. 

 Stalks short, up to 1 mm. long, usually recumbent, slender, black, 

 continuing into a more or less slender, crooked columella extend- 

 ing nearly to the summit of the sporangium, or dissipated. Capil- 

 litium dense, of dark brown threads, very irregular, sometimes 

 ending in a fairly defined surface-net with small meshes, or the 

 meshes may be larger, or the net absent. Spores 9-12 n diam., 

 rather dark, purplish brown, reticulate with raised bands, con- 

 tinuous or broken, or with spines. 



Type locality: Venezuela (Fendler). 



Habitat: On leaves, mosses, and sticks, in wet marshes. 



Distribution: Maine, New York, Ontario, Quebec, *South 

 Carolina, Virginia. 



