STEMONITIS 167 



umella; the main branches more and more numerous, thicker and ir- 

 regular towards the apex of the sporangium, and often form irregular 

 flattened expansions" : — etc. This suggests some form of S. dictyo- 

 spora Rost. : see under our No. 5. Possibly for such reasons Lister 

 referred it to 5. splendens Rost., which as we have just seen, was un- 

 doubtedly regarded by the author as a form of the fuscous group. 



The long, slender, simple columella is not only lateral, but occupies 

 indeed the sharp vertical angle of the triangular, prismatic sporan- 

 gium. Furthermore, the sporangium is at maturity strangely twisted, 

 so that the columella in its ascent accomplishes one or more spiral 

 turns. In forms collected by Dr. Rex, which seemed to him most 

 nearly to agree with Massee's species, the inner capillitium is some- 

 what abundant, but the character of the columella just the same. 



Pennsylvania, Ohio, Kansas, Colorado, Iowa; India! 



11. Stemonitis smithii Macbr. 



1893. Stemonitis smithii Macbr., Bull. Lab. Nat. Hist. la., II., p. 381. 



1894. Stemonitis microspora List., Morg., Jour. Cin. Soc, p. 54. 



1911. Stemonitis ferruginea var. smithii Lister, Mycetozoa, 2nd ed., p. 150. 



Sporangia in small clusters, close-packed and erect, not spreading, 

 bright ferruginous prior to spore dispersal, cylindric, stipitate, of 

 varying height; stipe jet-black, shining, about one-third the total 

 height ; hypothallus generally well developed ; columella black, gradu- 

 ally tapering, at length dissolving in capillitial threads and net some 

 distance below the diminished plumose apex ; capillitium of fuscous 

 threads, the inner network of abundant, sparingly united branches 

 uniformly thickened, the surface net very delicate, composed of small, 

 regular, polygonal meshes, the peridial processes few; spore-mass 

 bright ferruginous, spores by transmitted light pale, almost colorless, 

 smooth, 4-5 /A. 



The species as thus constituted includes forms varying in size from 

 2.5-3 mm. only. The common form heretofore known everywhere 

 in America as S. ferruginea is from 10-15 mm. high. The type to 

 which the specific name S. smithij. was originally applied is 2.5 mm. 

 high and rejoices in smooth, almost colorless spores, 4-5 {x. 



The Plasmodium in the case of the species now considered is as 



