360 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
at base of inflorescence and then forming more conspicuous often 
nodular swellings one to several centimeters in length, with dehis¬ 
cence of the thin smooth membrane disclosing dusty olive brown 
spore mass; spores chiefly ovoid to spherical, occasionally more 
irregular, usually prominently echinulate, 9-12 p, rarely most elon¬ 
gated 15 /a, in length. 
Hosts: Panicum proliferum , la., Ill., Kans., Miss, (type); P. 
mrgatum , Tex. 
This is very closely related to Ustilago sphaerogena from which 
it differs in the smaller sori (when they occur in the ovaries), in 
its development on various parts of the host, and in the smooth 
membrane which covers the sorus. The spores are about the same 
in the two species. The germination has not been described but 
has been found by the writer to be about like that of Ustilago 
sphaerogena. Literature: 181. 
Ustilago sphaerogena Burr. 
Ustilago sphaerogena Burr., 1 Ell. & Ev., N. A. Fungi, 1892. 1887. 
Cintractia sphaerogena Hume, Proc. Ia. Acad. Sci., 9 : 233. 1902. 
Exsiccati : Ustilago sphaerogena Burr., on Panicum Crus-galli , Ell. & 
Ev., N. A. Fungi, 1892, Seym. & Earle, Econ. Fungi Clinton Ust. Supp., 
C 88, Rab.-Wint.-Paz., Fungi Eur., 4307. 
Sori in ovaries, ovate, 4-10 mm. in length, covered with a tough 
hispid membrane which ruptures irregularly from apex disclosing at 
first an agglutinated but finally a dusty, olive brown spore mass ; 
spores ovoid to subspherical, prominently and sharply echinulate, 
chiefly 9-12 p in length. 
Host: Panicum Crus-galli, Conn., Ia. (type C. sphaerogena), 
Ill. (type), Mo., Neb., N. Car.; Mex. (Jalisco). 
This fungus usually occupies only a few of the ovaries of the 
inflorescence and these are generally in the same region. It is often 
associated with Tolyposporium bullatum and as they both occupy 
the ovaries and are often of the same size they are sometimes con¬ 
fused. They can be distinguished easily, however, as the former 
usually produces larger, harder sori which are covered by a hispid 
membrane while the thinner membrane of the latter is smooth. 
1 The first description of-this species seems to be that in Sacc., Syll. Fung., 
7 2 : 468. 1888. 
