170 Illinois State Laboratory of Natural History. 



turned side wise, beak-like; not seldom double; and occasionally 

 suggesting the appendages at the apex of the teleutospores of 

 Puccinia coronata. 



U. graminicola, Burrill. 



II., III. Sori amphigenous, but more common on under 

 surface, scattered, small, oblong or linear, soon uncovered, the 

 ruptured epidermis ragged, but usually its remains plainly ap- 

 parent. Uredosori yellow, teleutosori blackish brown; uredo- 

 spores spheroidal or oval, minutely echinulate, 15-18 by 18-22 P. 

 Teleutospores variable, subglobose, oval or oblong, smooth; 

 apex rounded or angular, thickened, 12-18 by 21-30 ^; pedicel 

 somewhat colored, thick, scarcely tapering below, once to twice 

 the length of the spore. 



On Panicum virgatmn : McLean, July 20, 2847, II., III., 

 Oct. 11, 1832; Champaign, Aug. 13, 1036, II., III.; McHenry, 

 Sept. 1, 1407. Elymus virginicus: Piatt, Aug. 10, 1001. 



This species resembles somewhat closely U.jnnci, (Schw.) 

 Tul., from which, however, it is sufficiently distinct aside from 

 the difference in host. Compared with the latter the present 

 species has larger and sooner opened sori, the uredospores have 

 finer echinulations, and the teleutospores are usually shorter, 

 rounder, with apex less produced and pedicel very distinct, 

 being thicker, longer, and less tapering below. Among the 

 Uromycetes on grasses this seems distinct from V. Peckianu*, 

 Farlow, to which it bears some resemblance. The latter has 

 the teleutospores more nearly subglobose, epispore uniformly 

 thickened, not produced at apex, and with longer and differ- 

 ent pedicels. Perhaps the nearest approach is to U. spartina j , 

 Farlow, which, however, has much larger and thicker-walled 

 uredospores, and the teleutospores are lighter colored, more 

 regular in shape, with longer and more slender pedicels. 



PUCCINIA, PEKS. 



Teleutospores two-celled, one above the other, brown, pro- 

 duced on permanent pedicels which arise in dense masses from 

 a cushion-like layer of irregular cells beneath the epidermis. 



The characteristics of the genera Uromi/ces and Puccinia 



