ON GRAMINE.E 



251 



often confluent and reaching a length of 1 cm. or more, 

 surrounded by the cleft epidermis, pulverulent, yellow-brown ; 

 spores ellipsoid or ovate-oblong, echinulate, yellow-brown, then 

 yellowish, 22 — 42 x 16 — 22 /x, generally with four equatorial 

 germ-pores. 



Fig. 193. P. grami nis. a, aecidia 

 on Berberix ; b, nredo- and c, 

 teleutospores on wheat. 



Fig. 194. P. graminis. 

 Teleuto- and uredo- 

 spore on Aira caexpi- 



toxa . 



Teleutospores. Sori similar, but forming long lines, soon 

 naked, pulvinate, black ; spores oblong-clavate, rounded or atten- 

 uated at the summit, much thickened (6 — 13 fi), slightly con- 

 stricted, attenuated below, smooth, chestnut-brown, 35 — 60 x 

 12 — 22/*; pedicels brownish, persistent, thick, as much as 60 //. 

 long ; paraphyses always absent. 



/Ecidia on leaves and fruits of Berberis vulgaris and Mahonia 

 Aquifolium ; uredo- and teleutospores on Agropyron caninum, 

 A. repens, Agrostis alba, A. canina, A. vulgaris, Aira caespitosa, 



A. flexuosa, Alopecurus pratensis, Arrhenatherum elatius, Avena 

 fatua, A. saliva, Brack y podium pinnatum, Bronius arvensis, 



B. asper, B. erectus, B. giganteus, B. mollis, B. secalinus, Dac- 

 tylis glomerata, Festuca Myurus, F. ovina, F. rubra, Holcus 

 lanatus, H. mollis, Hordeum murinum, H. pratense, B. vulgare, 

 Lolium perenne, Milium effusum, Molinia caerulea, Phalaris 

 canariensis, Poa compressa, P. nemoralis, P. pratensis, P. 



