Comprehensive Description
provided by North American Flora
Nigredo pyriformis (Cooke) Arthur
Uromyces pyriformis Cooke ; Peck, Ann. Rep. N. Y. State Mus. 29 : 69. 1878. O and I. Pycnia and aecia unknown.
Uredinia amphigenous, solitary or sometimes more or less confluent in irregular or oval groups, oval or oblong, 0.2-0.4 mm. wide by 0.5-1 mm. or more long, early naked, pulverulent, cinnamon-brown, ruptured epidermis conspicuous ; urediniospores obovoid or ellipsoid, 18-19 by 21-26 /x; wall light cinnamon-brown, 1.5-2 /x thick, evenly and rather moderately echinulate, the pores usually 2, sometimes 3, approximately equatorial.
- bibliographic citation
- Joseph Charles Arthur, Frank Dunn Kern. 1912. (UREDINALES); AECIDIACEAE (continuatio), GYMNOSPORANGIUM. North American flora. vol 7(3). New York Botanical Garden, New York, NY
