PUCCINIA 307 



Uredo sori minute, yellow-brown, densely crowded on the 

 leaves, more scattered on the inner surface of the glumes ; 

 spores globose or broadly elliptical, spinulose, yellow, 25-30 fj, 

 diam. 



Teleutospore sori forming crowded blackish streaks on the 

 leaf-sheaths, more scattered on the inner surface of the 

 glumes, encircled with curved, brownish paraphyses; spores 

 unsym metrical, apex flattened or with 1-2 blunt prominences 

 30-40 //, long, basal cell 9-12 /x wide, terminal cell 16-24 /x 

 wide ; promycelial contents yellow. 



Puccinia simplex (Eriks. and Henn.) produces uredo 

 and teleutospores on leaves of barley. Aecidium unknown. 



Uredo sori very minute, up to 0*5 mm. long, sparing, 

 scattered on upper side of leaves, citron-yellow ; spores 

 globose or shortly elliptical, spinulose, yellow, 19-22 /* diam., 

 or 22-27 * I 5~ I 9 /* 



Teleutospore sori very minute, blackish, scattered on the 

 leaves, somewhat longer on the leaf-sheath, surrounded with 

 brown paraphyses ; spores stipitate, mostly i-celled, unsym- 

 metrical, 24-30 x 16-18 /*, rarely 2-celled, clavate, apex blunt 

 or narrowed, 40-48 //, long, basal cell 16-18 /x broad, terminal 

 cell 19-24 p broad. 



Puccinia phlei-pratensis (Eriks. and Henn.) occurs in a wild 

 state on timothy grass (Phleum pratense), but artificial infec- 

 tion has shown that it can infect cultivated cereals. The 

 aecidium stage is unknown. 



Uredo sori often crowded, yellowish-brown, 1-2 mm. long, 

 on leaf-sheath and culm; spores oblong or pear-shaped, 

 spinulose, dirty yellow, 18-27 x 15-19 /A. 



Teleutospore sori blackish, on leaf-sheath and culm, 

 2-5 mm. long ; spores fusiform or club-shaped, constricted at 

 the septum, chestnut-brown, apex rounded or narrowed, wall 

 much thickened, 38-52 x 14-16 ju. 



Brachypuccinia. Spermogonia, uredospores and teleuto- 

 spores produced on the same host, aecidia absent. 



Celery rust (Puccinia bullata. Winter) forms small warts 

 on the leaves of celery, parsley, dill, and on several wild 

 umbelliferous plants. When the epidermis is ruptured the 

 spore-mass is brown. The fungus is destructive when present 

 in quantity. 



Spermogonia arranged in rounded groups. 



