202 NATURAL HISTOEY BULLETIN 



Plants are gregarious and occur in large numbers. Similar 

 forms occur on various kinds of herbaceous stems in wet places. 



HELOTIUM Fries, Summa Veg. Scand, 354. 1849. 



Plants generally gregarious, stipitate or sessile; stem when 

 present short, stout; substance waxy, bright colored; hymenium 

 concave or convex; asci 8-spored; spores elliptical or fusiform, 

 ends blunt or sharp-pointed, simple or occasionally pseudo-sep- 

 tate ; paraphyses slender ; for the most part small plants growing 

 on wood, stems and leaves. 



Several species occur in Iowa, three of which have been studied. 



KEY TO THE SPECIES. 



Plants more or less stipitate. 



Plants deep lemon yellow; stem very stout, on 



old wood B. citrinum. 



Plants pale yellow, stem more slender or want- 

 ing, on decaying leaves H. friesii. 



Plants entirely sessile, on dead stems of Carex. .H. citrinulum seaveri. 



*Helotium citrinum (Hedw.) Fries, Summa Veg. Scand. 355. 

 1849. 



Plate 20, f. i. 



Octospora citrina Hedw., Laub-Moose 2: 33. 1789. 



Helotium friesii (Weinm.) Sacc, Syll. Fungi 8: 228. 1889. 



Plate 23, f . n. 



Peziza friesii Weinm., Hymeno-Gastero-Mycetes 469. 1836. 



Plants 1 to 2 mm. in diameter, usually with a short stem but 

 often nearly sessile; hymenium plane or convex, pale yellow, 

 when dry rather deep yellow, color resembling that of the pre- 

 ceding but much paler ; asci clavate, 65 to 70 by 5 to 6/*, 8-spored ; 

 spores slightly clavate, 8 to 9 by 3 to 4/x,; paraphyses filiform, 

 slender. 



On decaying leaves of Populus sp. in damp place in woods, 

 Iowa City. 



The plants described here under this name were abundant on 

 the substratum named above, and while the microscopic charac- 

 ters of the species under which this is here described are not 

 mentioned in the original description, the plants correspond well 

 in external characters. 



