140 THE NORTH AMERICAN SLIME-MOULDS 



threads, reddish brown ; capillitium scanty, white, or colorless, simple 

 or sparingly branched; spores dark violaceous, spinulose, 12-13 fi. 



This is Chondrioderma aculeaturn Rex, Proc. Acad. Nat. Sci. Phil., 

 1891, p. 390. After careful comparison of specimens and various 

 descriptions, especially that of Rostafinski with the type specimens of 

 Dr. Rex, I am constrained to concur with Lister in adopting Rosta- 

 finski's name. The sporangia in the type specimens (Rex) are on 

 moss, borne at the extreme tips of acuminate or aculeate leaves, so 

 that at first sight they appear stipitate. 



Apparently rare. Maine, New York. 



12. DiDERMA COR-RUBRUM Macbr. 71. S. 



Plate XVIII., Fig. 2 



Sporangia gregarious clustered, small .5-7 mm., sessile corrugate- 

 plicate, especially above, snow-white, the outer peridium cartilaginous 

 polished without and within, the inner delicate, evanescent ; columella 

 well developed, globose or clavate, anchored by several stout trans- 

 verse trabecules to the peridial wall, papillate, deep-red as is the 

 peridium especially below; capillitium very delicate, sparingly 

 branching, colorless; spores verruculose, fuliginous tinged with red, 

 about 12 fx. 



This curious but elegant little species is represented by a single 

 colony collected by Professor Morton Peck in Iowa. It resembles 

 D. sauteri but is distinguished by the plicate white wall, the stout 

 columella with its lateral extensions, as by the more delicate spores. 

 On rotten wood. 



13. DiDERMA OCHRACEUM Hojfm. 



1795. Diderma ochraceum Hoffm., Deutsch. FL Tab. 9, 2, b. 

 1911. Diderma ochraceum Hoffm., List, Mycetozoa, 2nd ed., p. 109. 



Sporangia gregarious or clustered, .7-1 mm., sessile, globose or 

 sometimes plasmodiocarpous, ochraceous yellow; outer wall cartilag- 

 inous with yellow deposits of lime, the inner also yellow, adherent 

 or free; columella not distinct; capillitium simple or branching, 

 purple-brown, hyaline at base ; spores spinulose, purplish-grey, 9-1 1 fx. 



Mr. Lister reports this species from Massachusetts. 



