Report of the Botanist. 12 L 



33. P. OBTECTA Pech. Hidden Brand. 



Cauline; sori unequal, often very large, angular or orbicular, 

 scattered or confluent, slightly elevated, long covered by the 

 epidermis, black ; spores oblong or oblong-clavate, sometimes 

 curved, constricted, obtuse or obtusely pointed, .0018'-.0024:' long, 

 .0008' broad ; peduncle colored, seldom half as long as the spore. 



Stems of the lake rush, SgIpj>ii.s vcdidas. AYatkins and Monte- 

 zuma marshes. September. Also on Scii'jnts piongens. Albany. 

 October. 



The green stems of the rush are often mottled by discolored 

 spots, a sterile or imperfect state of this fungus, but 1 have found 

 fertile specimens on very old dead stems only. 



« 



3i. P. coEONATA Cd. Crowned Brand. Mildew. 



Amphigenous ; spots pallid or yellowish; sori narrow, oblong or 

 linear, crowded, long covered by the epidermis, then surrounded 

 by its ruptured remains, black; spores oblong, not constricted, 

 mostly tapering toward the base, truncate at the apex and crowned 

 with a few prominent blunt tooth-like processes, .0016'-.0022 

 long, .0006' broad ; peduncle colored, very short. 



Leaves of grasses and cereals. Common. August and Septem- 

 ber. 



This species is well marked by the apical crowa of teeth. 



35. P. LINEARIS Pech. Linear Grass Brand. 



Amphigenous ; sori very narrow, deeply seated, oblong or linear, 

 parallel, crowded, long covered by the epidermis, black ; spores 

 oblong, slightly tapering toward the base, not constricted, very 

 obtuse or truncate, .00 18'-. 0021' long, .0006' broad ; peduncle 

 colored, very short. 



Leaves and sheaths of grasses. Watkins. September. 



This is closely related to the preceding species but is without 

 the apical teeth of the spore. 



36. P. GEAMiNis Pers. Grass Brand. Corn Mildew. 

 Amphigenous ; sori oblong or linear, crowded or confluent, often 



parallel, surrounded by the ruptured epidermis, black ; spores 

 obovate oblong or oblong-clavate, slightly constricted, generally 

 obtusely pointed, sometimes obtuse, .0016'-.0024:' long, .0006' 

 broad; peduncle colored, one-half to wholly as long as the spore. 



Leaves and sheaths of grasses and cereals. Yery common and 

 variable. Autumn and spring. 



Probably this Puccinia is more injurious to the interests of the 

 farmer than any other. Its Uredo form is the Uredo Pid)igo of 

 16 



