186 British Uredinee and Ustilaginea. 
Puccinia centaurez. Mart. 
Spermogonia—On yellow spots, which are round on the leaves, 
elliptical or lanceolate on the petioles, where they are surrounded 
by a purple margin. 
Uredospores—Primary : Sori few, surrounded by the spermogonia, 
large, round or elliptical. Spores produced singly on basidia, 
globose or subovate, echinulate, brown, about 254 -across. 
Secondary : Sori small, very numerous, scattered, mostly hypo- 
phyllous, dark brown, soon pulverulent. Spores subglobose 
or elliptical, brown, echinulate, 20-25 X 16-23. 
Teleutospores—Sori very small, amphigenous, roundish or oval, 
black, pulverulent, often confluent. Spores elliptical, pyriform, 
or subglobose, not constricted, both cells equal or nearly so, 
dark brown, smooth, 30-50 x 20-28u. Pedicels hyaline, 
short. 
Synonyms. 
Puccinia centauree. Mart., “ Flor. Mosg.,” p. 226. Cooke, 
“ Micro. Fungi,” 4th edit, p. 207. Grev., “Flor. Edin.,” p. 430. 
Puccinia compositarum, Mart., in part. Berk., ‘‘ Eng. Flor.,” 
vol. v. p. 365. Johnst., ‘Flor. Berw.,” vol. ii, p. 196. Cooke, 
“ Hdbk.,” p. 499. 
Exsiccatt. 
Vize, ‘‘ Micro. Fungi Brit.,” 120. 
On Centaurea nigra. 
BioLocy.—The primary uredospores, accompanied by the spermo- 
gonia, occur early in May, and are in very much larger sori than the 
secondary uredospores.- I found by experimental culture that the 
primary uredospores produced the secondary in about fourteen days 
(Exp. 851, 852), but that no result followed when they were applied 
to Zaraxacum officinale (853), Leontodon autumnalis (923), and 
Hieracium pilosella (854, 855). 
Puccinia taraxaci. Plow. 
Spermogonia—On yellow oval or rounded spots. Paraphyses not 
conspicuous. Spermatia globose or oval, r—-2y in diameter. 
Uredospores—Primary » Sori scanty, large, dark brown, elongated 
