228 



MANUAL OF POISONOUS PLANTS 



surrounded by paraphyses. Spores with short pedicels, mostly club-shaped, 

 unsymmetrical; apex somewhat truncate, or with one or two projections. 



Distribution. Common in Europe and probably also m this country; has 

 usually been referred to as Puccinia rubigo-vera. In European mycological 

 works, the aecidium of this fungus is said to be very common on common 

 speedwell (Lithospermum arvense), Bchium vulgar e, and Anchusa offiamhs. 



Fig. 64. Forms of rust on cereals. A. Common wheat rust, Puccinia gramims on- 

 sheath of wheat, winter spores germinating. B. The same, sporidia sp. C. Epidemw* 

 under surface of leaf with sporidium, sp. and germ tube. i. penetrating the epidermis.^ D. 

 Uredospore germinating after being in water 14 hours in E. Puccinia rubigo-vera germinat- 

 ing. F. Puccinia graminis. Both cells have germinated, a, sporidium germinating, magni- 

 fied X 600. G. Crowned rust (P. coronata) from oat leaf; G after BoUeyj the remainder, 

 DeBary. 



