CLINTON: NORTH AMERICAN USTILAGINEAE. 
411 
This genus is characterized by the rather temporary spore balls, 
often entirely separating at maturity in which case they cannot be 
disti nguished from Ustilago. Species have been described some¬ 
what indiscriminately under Sorosporium, Thecaphora and Tolypo- 
•sporimn so that these genera need a careful revision. In a few cases, 
however, it is difficult to determine the generic position. Very 
often the sori are provided with a false membrane similar to that 
of Sphacelotheca. Saccardo has described 32 species of Sorospor¬ 
ium ; 9 are given here. Their hosts are chiefly among the Gram- 
ineae. 
Sorosporium consanguineum Ell. & Ev. 
Ustilago Aristidae Pk., Bull. Torr. Bot. Club, 12 : 35. 1885. 
Sorosporium consanguineum Ell. & Ev., Journ. Myc., 3 : 56. 1887. 
Exsiccati: Ustilago Aristidae Pk., on Aristida longiseta robusta , Ell. & 
Ev., Fungi Col., 1600, on Aristida Scheideana, Griff., West Amer. Fungi, 
214, 214a. 
Sori in ovaries, entirely enclosed by glumes though often some¬ 
what visible through these ; spore balls oblong to subspherical, more 
or less irregular, at first firm but with age usually becoming entirely 
dissolved, about 80-135 g in length ; spores reddish brown, ovoid 
to subspherical but chiefly polyhedral, smooth, mostly 6-9 g in 
length. 
Hosts: Aristida basiramea , S. Dak.; A. longiseta, var. robusta, 
Neb.; A. purpurea, Neb.; A. Rusbyi, Ariz. (type S. consangui¬ 
neum ,); A. Scheideana , Ariz.; Aristida sp., Ivans., Tex. (type U. 
Aristidae ). 
An examination of the types of both Peck’s and Ellis and Ever¬ 
hart’s species show them to be the same and both witli rather firm 
spore balls. A number of other specimens examined agreed with 
these in all respects except there was little or no evidence of spore- 
balls. This condition is evidently only the result of advanced age 
or maturity, the spore balls having gone to pieces, and so all such 
forms have also been included here. Magnus and Brefeld have 
each described smuts on Aristida of about the same spore measure¬ 
ment as tliis species, but specimens have not been available for care¬ 
ful comparison. Saccardo reports in the Host Index of the Syllogye 
Fungorum, Sorosporium Aristidae Neg., but no description is given. 
