418 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
with a dusty spore mass; spore balls composed of few to many fer¬ 
tile cells , rather permanently united, of small to medium large size ; 
spores usually yellowish or reddish , smooth on contiguous sides but 
usually marked on free surface; germination, so far as known, by 
means of a single sporidium at tip of the elongated septate promy¬ 
celium. 
As stated before, this genus is often confused with Sorosporium. 
The yellowish to reddish colored spores, smooth on their united 
sides but usually marked on the free, and the rather firm spore balls 
are the general characters by which the species may be told. Very 
few have been germinated and so it cannot be stated positively that 
the elongated proinyfcelium with a single terminal sporidium is a 
general characteristic. Saccardo describes 21 species ; 9 species are 
reported here, of which 5 occur on the Compositae. 
Thecaphora pilulaeformis B. & C. 
Thecaphora pilulaeformis B. & C., Grev., 3 : 58. 1874. 
Tolyposporium Davidsonii Diet. & Holw., Bot. Gaz., 19 : 305. 1894. 
Poikilosporium Davidsohnii Diet., Elora, 83: 87. 1897. 
Poecilosporium Davidsohnii Sacc. & Syd., Syll. Fung., 16 : 380. 1902. 
Sorosporium Bigeloviae Griff., Bull. Torr. Bot. Club, 29: 295. 1902. 
Exsiccati : Sorosporium Bigeloviae Griff., on Bigelovia, Griff., West 
Amer. Fungi, 399. 
Sori taking the place of the aborted inflorescence or often at the 
base of the leaves, subspherical, small, forming firm usually clus¬ 
tered pustules, upon dehiscence disclosing light colored spore mass ; 
spore balls somewhat irregular, chiefly 2-6 celled, 14-25 p in length ; 
spores yellowish, quite variable through pressure, oblong to poly¬ 
hedral or often three sided in cross section, with contiguous sides 
flattened and smooth but with curved free surface rather abundantly 
verruculose, chiefly 11-16 p in length. 
Hosts: Bigelovia veneta, Calif, (type); Bigelovia sp., Ariz. (type 
/ S . Bigeloviae) . 
1 his species was first described as Thecaphora pilulaeformis by 
Berkeley and Curtis on an unknown Compositae collected by 
Coulter in California. Twenty years later it was redescribed as a 
new species b}' Dietel and Holway on a supposed species of Atri- 
plex from the same State. Dietel later made the fungus the basis 
