ARCYRIA 265 



it is distinguished by the larger sporangia, smaller spores and the 

 character of the capillitium as well as by the color. 

 Philadelphia, Long Island, Iowa, Wisconsin. 



2. Arcyria gerstedtii Rost. 



Mon. 278. 1875. 

 PI. XVII, Figs. 450, 451, 452. 



1888. Hemiarcyria fuliginea Cooke & Mass., Grev. 16 : 74. 

 1892. Arcyria fuliginea (Cooke & Mass.) Massee, Mon. 169. 



Sporangia cylindric, arcuate, 1.5 mm. high when unexpanded, 

 4-6 mm. when expanded, closely clustered, dull crimson to almost 

 vermilion, stipitate; peridium evanescent except here and there a 

 persistent patch; calyculus shallow, plicate, papillose within; stipe 

 short, weak, concolorous; hypothallus distinct, membranous, con- 

 colorous; capillitium a loose, far expanding, elastic net, very easily 

 detached, the meshes uneven, often small, the threads characterized 

 by much irregularity and many bulbous thickenings, especially at the 

 nodes, strongly spinulose throughout; spore-mass crimson or reddish 

 brown, dull; spores by transmitted light colorless, minutely spinulose, 

 subglobose, 8-10 ix. Plasmodium at first colorless, then white, finally 

 becoming red when the sporangia begin to form. 



Rostafinski's fig. 196 is excellent and gives the idea of what we regard 

 the typical marking of the capillitium. Externally the species resembles 

 somewhat A. nodulosa, and the network of the capillitium is also 

 suggestive of that form; the spiny capillitium is unique. 



Rare in the United States: New York, Pennsylvania, Washington, 

 Oregon. Widely distributed, reported from all the continents except 

 South America. 



3. Arcyria nutans (Bull.) Grev. 



Fl. Edin. 455. 1824. 

 PI. XVII, Figs. 453, 454, 455. 



1791. Trichia nutans Bull., Champ. 122. 



1791. Stemonitis nutans (Bull.) Gmel., Syst. Nat. 2 : 1467. 



1794. Arcyria flava Pers., Roemer N. Mag. Bot. 1 : 90. 



1797. Stemonitis amcena Trent, in Roth, Cat. Bot. 1 : 222. 



1803. Trichia elongata Schum., Enum. PI. Saell. 2 : 209. 



1803. Arcyria alutacea Schum., Enum. PI. Saell. 2 : 212. 



Sporangia crowded, cylindric, about 2 mm. high when unexpanded, 

 4-6 mm. when expanded, pale yellow or buff, short-stipitate or sessile 

 by an acute base; peridium wholly evanescent, except at the base, 

 where persists the shallow, colorless, often inwardly spinulose, plicatu- 



