33(1 PROCEEDINGS : BOSTON SOCIETY NATURAL HISTORY, 
ii. Spores chiefly in pairs. 
A. Sori agglutinated (on leaves) .... Schizonella 
B. Sori dusty (inside peduncles) .... MyJcosyrinx 
hi. Spores in balls. 
A. Sori dusty or granular. 
1. Spore balls often evanescent; spores olive or black brown 
Sorosporium 
2. Spore balls rather permanent; spores yellowish or reddish, 
with markings only on free surface . Thecciphora 
3. Spore balls quite permanent; spores adhering by folds or 
thickenings of outer coat . . Tolyposporium 
B. Sori agglutinated. 
1. Spore balls (variable) composed of thick walled spores 
Tolyposporella 
2. Spore balls with peripheral spores and central sterile cells 
Testiculciria 
Under the above 11 genera, 129 species, with varieties, are de¬ 
scribed here from North America. 
Ustilago Rouss. 1 
FI. clu Calv., 47. 1806. 
( Necrosis Paul., Traite des Champ., 1: 548. 1793.) 
(Ustilago Pers., Syn. Fung., 224. 1801. Sub-genus.) 
(Ustilagidium Herzb., Zopf Beitr. Phys. Morph. Org., 5 : 7. 1895.) 
Type: Ustilago segetum Pers. 
Host: Gramineae. Fr. 
Sori on various parts of the hosts, at maturity forming dusty r 
usually dark colored spore masses / spores single , produced irregu¬ 
larly in the fertile mycelial threads which early entirely disappear 
through gelatinization ; small to medium in size ; germination by 
1 Bauhin, Hist. Plant., 2: 418, in 1651, is really the founder of Ustilago. 
Fries or Persoon is ordinarily cited as the authority for the genus. Fries used 
Ustilago as a genus in his Syst. Myc., 3 : 517, in 1829, with U. grandis as the 
first species. Persoon used Ustilago as a subgenus under Uredo with Uredo 
segetum as the first species having five varieties of which a U. Hordei is first. 
Paulet’s name, Necrosis, cannot be regarded as a true generic name, but was 
used more as a descriptive term. 
