416 



GRASS-RUST. 

 RUSTS. 



3 Grass-rust, {Puccmia graminis, P.) Order Basidiomy 

 cetes. Sub-order Uredineae. 



Fig. 160.— Several stages of grass-rust. A, young aecidium fruit; x, section of Bar- 

 berry leaf; a p. secidium fruit; s p, sperinagonia; 17., a mass of teleutospores on a leaf 

 of a grass; III., three uredospores, u r; with one teleutospore, (. — (From DeBarry.) 



Forming orange-red, powdery spots and lines on the leaves 

 and stems of cereals and meadow-grasses, that give place later to 

 dead-black velvety lines. 



The sheaths and culms of the smaller grasses, especially quack 

 grasses and red-top, are very often attacked by this rust (called 

 mildew and brand in England), which produces the same dis- 



