CLINTON: NORTH AMERICAN USTILAGINEAE. 
347 
Ustilago Miihlenbergiae P. Henn. 
Ustilago Miihlenbergiae P. Henn., Hedw., Beibl., 41: 61. Apr. 1902. 
Ustilago Muhlenbergiae Clint., Journ. Myc., 8 : 133. Oct. 1902. 
Sori in the abortive inflorescence, ovoid to subspherical, about 
3-6 mm. in length, protected by thin semitransparent membrane of 
the infected floral parts, upon rupture disclosing black brown dusty 
spore mass; spores rather dark reddish brown, chiefly spherical, at 
first apparently smooth, but with age or approaching germination 
splitting off caps on opposite sides of epispore and these eventually 
breaking up into small granular echinulations thus leaving a dark, 
less broken central band, 4-6 p, in diameter. 
Hosts: Muhlenbergia Pringlet, N. Mex. (type) ; M. Texana , 
Ariz. (type U. Muhlenbergiae Clint.). 
Hennings’ description of this species appeared after the writer’s 
description was in manuscript and so was overlooked at time of 
publication. Since then specimens from which Hennings described 
his species have been received from Hennings and also from Hol- 
way and they show the species to be the same, in all probability. 
There is a difference in the appearance of the spores but this is 
apparently due to their age at time of collection. The Holway 
specimens show the spores with a smooth epispore but with a cap 
split off at either end, while the Farlow specimens, from which the 
writer described the species, show the epispore split up into small 
granular echinulations at these points, leaving a less broken and 
darker central band. This probably comes from a preliminary swell¬ 
ing before germination, as these spores also average slightly larger. 
Their germination has not been reported. 
Ustilago residua Clint. 
Ustilago segetum Auct. p. p. 
Ustilago segetum f. Banthoniae Ell. & Ev., N. A. Fungi, 1893a. 1887. 
Ustilago residua Clint., Journ. Myc., 8: 133. 1902. 
Exsiccati: Ustilago segetum f. Banthoniae on Banthonia spicata, Ell. & 
Ev., N. A. Fungi, 1893a. 
Sori in the inflorescence, prominent, infecting the whole or some¬ 
times confined to the individual spikelets, usually enclosed by leaf 
sheaths, on exposure showing as olive brown dusty spore mass ; 
spores rather light olive brown, ovoid or ovate to spherical or occa- 
