242 Mycetozoa of North America 



and was described by Massee, based on a specimen from Java, as 

 Hemiarcyria stipitata. In the cooler months of autumn, the more 

 robust forms with short, stout stalks and deep cups will be found 

 and are usually regarded as typical. The phases are connected 

 by intermediate forms. In late autumn and winter, if subjected 

 to frosts, the sporangia may be sessile or nearly so, and the color, 

 sporangial wall, capillitium, and spores may show alterations from 

 their usual characters. Such developments are rarely alike, and 

 vary depending on the period and locality. Morgan proposed 

 four distinct species on abnormal forms, three of which are repre- 

 sented by type material here. Prof. G. W. Martin has kindly 

 furnished a specimen collected in the vicinity of Mt. Rainier, 

 Washington, and determined by him as H. montana. The four 

 "species" of Morgan appear to have developed in frosty weather, 

 and similar phases may be found almost anywhere during the 

 late autumn or winter. I have studied H. clavata in the field for 

 years, and examined particular logs periodically in order to note 

 the different variations that occur as the season advances into 

 the winter. All forms mentioned are only phases of H. clavata, 

 in my opinion. The reader is referred to the Lister Monograph 

 for further comments. 



4. Hemitrichia leiocarpa (Cooke) Lister, Mycetozoa 177, 1894. 

 Hemiarcyria leiocarpa Cooke, Ann. Lye. Nat. Hist. N. Y. 11: 405. 1877. 



Plasmodium? Total height 1.5 mm. Sporangia scattered, 

 stalked, obovoid, rarely subglobose, pale gray or ochraceous gray, 

 0.7 mm. diam. ; sporangial wall evanescent above, persistent below 

 as a cup, smooth or marked on the inside with short, scattered 

 ridges, forming a broken reticulation, colorless, longitudinally 

 plicate, minutely wrinkled transversely. Stalk 0.7 to 1 mm. long, 

 0.05 mm. thick, furrowed, ochraceous gray, containing spore-like 

 cells. Capillitium a network of frequently branching, pale gray 

 threads 2-5 n thick, marked with three to five often prominent, 

 dextral, spiral bands, either smooth or studded in many parts with 

 numerous spines about 2 (x long; free ends subclavate, usually 

 spinulose. Spores smooth, pale gray in mass, 6-8 /n diam. 



Type locality: Maine. 



Habitat: On dead wood, mosses, and leaves. 



Distribution: *Maine, ^Ontario, Pennsylvania. 



