272 THE MYXOMYCETES 



as X 1000, shows most of them to range from 6-8 fx with only one 

 spore attaining 9 fx. 



13. Arcyria digitata (Schw.) Rosl. 



Mon. 274. 1875. 

 PL XVIII, Figs. 471, 472. 



1832. Stemonitis digitata Schw., Trans. Am. Phil. Soc. II. 4 : 260. 



1855. Stemonitis grisea Opiz, Lotos 215. 



1855. Arcyria leprieuri Mont., Ann. Sc. Nat. Bot. IV. 3 : 141. 



1869. Arcyria bicolor Berk. & Curt., Jour. Linn. Soc. 10 : 349. 



1873. Arcyria pallida Berk. & Curt., Grev. 2 : 67. 



1876. Arcyria stricta Rost., Mon. App. 36. 



1925. Arcyria cinerea (Bull.) Pers. var. digitata (Schw.) G. List., Mycetozoa 

 ed. 3. 232. 



Sporangia gathered in tufts, 3-12 or more on a single stipe, the 

 clusters themselves scattered; individual sporangia elongate-cylindric, 

 2-4 mm. long, or rarely globose, ashen gray or nearly white, stipitate; 

 stipe as long as the sporangium, or longer, stout, sometimes showing 

 traces of consolidation of several, dark brown or black; capillitium 

 looser and more expanded than in A . cinerea, the threads more strongly 

 spinulose; spore-mass concolorous; spores under the lens globose, 

 colorless, with irregularly scattered warts, 7.5-8 fx. 



Closely related to the preceding species of which it is commonly 

 regarded as a variety, but different in habit and on the whole larger 

 and more robust throughout. The stipes in some cases are completely 

 merged in one; in others traces of coalescence remain. The number of 

 united sporangia varies. There are some clusters before us containing 

 16 and 18 in a single fascicle! 



New England, Pennsylvania, Ohio, South Dakota, Washington, 

 south to Brazil; Europe, the tropics generally. Not common in 

 temperate regions but abundant in the tropics. 



14. Arcyria carnea G. Lister 



Jour. Bot. 59 : 92. 1921. 

 1911. Arcyria cinerea (Bull.) Pers. var. carnea Lister, Mycetozoa ed. 2. 236. 



Sporangia stalked, loosely clustered, flesh colored, ovoid or short- 

 cylindrical, 1.5 mm. tall; calyculus marked with papillae or with a 

 broken reticulation, giving attachment to the capillitium; stalks short, 

 0.2-0.4 mm.; capillitium a compact network of pale flesh colored 

 threads about 3.5 n wide, marked with close-set prominences arranged 

 in a loose spiral and appearing truncate, notched or hammer-shaped 



