PERONOSPORA SEVMOURII Burrill n. sp.
Sparse, forming white patches or lines on leaves and stems ; oospores on floral organs. Mycelium large, distorted, haustoria knob-like ; conidiophores slender, seven' or eight times dichoto mous, branches flexuous, spreading, tips short or of moderate length, subulate ; conidia subglobose to elliptical, variable, by 14-27//, brownish; oi5gonia with firm, rather thick brownish walls, reaching 7o/t in diameter ; oospores dark brown, opaque, thick-walled, rough, 27-45 B.
On Houstonza sp. Union and Jackson counties, Illinois, April I t-28,1882. (A. B. Seymour.) The above description was furnished me by Professor T. J. Burrill. Having found what appeared to be an undescribed
species of Peronosporct on Houstonia patens, in Auburn, Alabama, I learned by accident that a species had been found on the same host many years ago and that its description written at the time by Mr. Seymour had laid in manuscript until now. The Alabama specimens appear to be the same species, but no oospores were found. In the Alabama specimens the conidiophores were about 400p long, with a diameter of about 6R; the branching was alter nate, the main branches being 70-90p long and the ultimate branches or sterigmata 6—lop ; the conidia were more often ovate, 21 by 11-14B.