198 Bulletin 313 



becoming darker with age, globoid, 120-140 [x; ostiolar filaments ap- 

 parently rather short.'' 



"I. Aecia hypophyllous, crowded in irregular groups 1-2.5 mm. 

 across, short, cupulate, 0.2-0.3 mm. in diameter peridium colorless, 

 erect, the margin lacerate; peridial cells rhomboidal, 13-19 by 29-34 

 fx, somewhat overlapping, the outer wall 4-6 ^i thick, transversely 

 striate, the inner wall, rather coarsely verrucose; seciospores glo- 

 boid, 21-26 by 21-28 ix; wall colorless, 1-1.5 fx, inconspicuously ver- 

 rucose," 



"II. Uredinia chiefly epiphyllous, numerous, scattered, roundish, 

 0.2-0.5 mm. across, tardily naked, pulverulent, light cinnamon- 

 brown, the over-arching epidermis ruptured by an uneven slit ; ured- 

 iniospores broadly ellipsoid, 18-24 by 26-32 /a; wall golden-brown, 

 1-2 IX, rather finely echinulate, the pores 2, opposite, equatorial. 



"III. Telia amphigenous and caulicolous, numerous, scattered, 

 crowded and confluent on stems, roundish or oval, 0.2-1 mm. across, 

 rather early naked, compact, pulvinate, blackish, ruptured epidermis 

 at first conspicuous, later disappearing; teliospores broadly ellip- 

 soid, 19-27 by 29-37 [x ; w^all dark chestnut-brown, thick, 2-3 ^x, with a 

 lighter-colored broad cap making the wall at the apex 6-10 fi thick, 

 smooth ; pedicel light-yellow, usually persistent, uniform, about 

 twice the length of the spores." North American Flora, v. 7, p. 266 

 (1912). 



1040. Teleutospores, 1/12. 



NiGREDO TRiFOLii (Hedw.) Arth. — On Trifolium repens. 



"O. Pycnia chiefly epiphyllous, in small groups or sometimes 

 spread out over larger areas, not conspicuous, honey-yellow becom- 

 ing reddish-brown, globoid, 100-130 fx in diameter; ostiolar filments 

 up to 30 IX long. 



''I. Aecia amphigenous, in roundish crowded groups or on the 

 veins and petioles in elongate groups, short, cupulate, 0.2-0.3 mm. in 

 diameter; peridium white, tlie margin erect or slightly recurved, 

 finely erose; peridial cells rhomboidal, slightly overlapping, 13-15 yu, 

 broad by 18-26 fx long, the outer wall rather thick, 5-6 fx, transversely 

 striate, smooth, the inner wall thinner, 2-3 |U,, moderately verrucose ; 

 aeciospores broadly ellipsoid or somewhat angular, 15-17 by 16-21 ix; 

 wall light-yellow or nearly colorless, thin, about 1 fx, finely verru- 

 cose." 



"II. Uredinia amphigenous, scattered, oval or roundish, 0.3-0.6 

 mm. in diameter, rather tardily naked, pulverulent, cinnamon- 



J 



