394 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
This is one of our most conspicuous but rather uncommon smuts. 
It has been introduced into this country, probably from Europe. 
Brefeld and Norton have described its germination. In one of his 
infection experiments Kellerman also got this developing on the 
leaves of corn, hence his form foliicola. Literature : 20, 27, 85, 97, 
109, 127, 129. 
* * Spores purplish. 
Sphacelotheca Hydropiperis (Schum.) DeBy. 
Uredo Hydropiperis Schum., Enum. PI. Saell., 2 : 234. 1803. 
Uredo bistortarum y Ustilaginea DC., El. Fi\, 6 : 76. 1815. p. p. 
Caeoma utriculosa Lk., Sp. PL, 6 2 : 9. 1825. p. p. 
Erysibe utriculosa Wallr., FI. Crypt. Germ., 2 : 216. 1833. p.p. 
Ustilago Candollei Tul., Ann. Sci. Nat., Bot., iii, 7 : 93. 1847. 
Ustilago Hydropiperis Schrot., Colin’s Beitr. Biol. Pflanz., 2 : 355. 1877. 
Sphacelotheca Hydropiperis DeBy., Yerg. Morph. Biol. Pilze, 187. 1884. 
Exsiccati : Sphacelotheca Hydropiperis (Schum.) DeBy., on Polygonum 
acre, Seym. & Earle, Econ. Fungi Clinton Ust. Supp., C 41, on Polygonum 
sagittatum, Shear, N. Y. Fungi, 85, Seym. & Earle, Econ. Fungi Clinton 
Ust. Supp., C 42, C 43, on Polygonum viviparum, Griff., West Amer. Fungi, 
223 ; Ustilago Candollei Tul., on Polygonum Hydropiper , Ell. & Ev., N. A. 
Fungi, 289, on Polygonum sagittatum, Thlim., Myc. Uni., 1018, Ell. & 
Ev., Fungi Col., 543 ; Ustilago Hydropiperis (Schum.), on Polygonum sag¬ 
ittatum, Ell. & Ev., N. A. Fungi, 2261, Ell. & Ev., Fungi Col., 336. 
Sori in ovaries, forming oblong or ovate bodies about 3-5 mm. in 
length, protected by floral envelopes at base, with false membrane 
dehiscing at apex, revealing purple black spore mass and more or 
less evident columella; sterile cells besides forming membrane also 
constitute part of the columella, spore-like (often probably imma¬ 
ture spores) hyaline or occasionally violet tinted, easily separating 
into individual cells, chiefly subspherical, 6-17 g ; spores purplish, 
broadly oblong or ovate but chiefly subspherical, very minutely but 
abundantly verruculose, mostly 10-17 g in length. 
Hosts: Polygonum acre, Ill., Mass.; P. Ilydropiper , Neb., R. I.; 
? P. Persicaria , N. Y.; P. sagittatum , Conn., la., Ill., Mass., Me., 
N. Y., Vt., W. Va.; P. viviparum , Wyo., Greenland; Polygonum 
sp., Mo. 
DeBary made this species the type of the genus. It differs from 
the other species incladed here in having the columella, as well as 
the false membrane, largely made up of sterile fungous cells. The 
