EXPLANATION OF PLATES. 



Plate I. — Comparative rustiness of four varieties of wheat from Uredo riibigo-vera 

 triiici, Garrett Park, Md. 1 Buckeye: a lower surface of leaf, 1) upper surface 

 of leaf; 2 Golden Prolific; 3 Gallauds Hybrid: a lower surface of leaf, b upper 

 surface of leaf; 4 Beloturka. The brown spots on .) and i were not caused by 

 rust. 



Plate II. — Yx and Theiss wheats rusted with Piicchua g7-ami)iis iritici and P.rubifjo- 

 vera irilici at Manhattan, Kans. 5 uredo of P. graminis; uredo and teleuto 

 stages of r. graminis; 7 teleuto stage of I\ graminis; 8 uredo and teleuto stages 

 of /'. riihigo-vera; 9 teleuto stage of P. ruhigo-vera. 



Plate III. — Cereal rusts produced by artificial infection on young plants. 10 Uredo 

 rubigo-vcra sccalis on rye; 11 U. ruhigo-vera secaJis on rye, showing how the 

 chlorophyll remains about rust spots during changes of the coloring matter; 1^ 

 U. ruhigo-vera secalis on Secale montanum; 13 TJ. rubigo-vera triiici on wheat; 

 14 U. coronaia on oats. 



Plate IV. — Cereal rusts produced by artificial infections on young plants. 15 Uredo 

 coronaia (a) and U. graminis arena' (b) produced on the samfe leaf of oats; 16 

 U. graminis arena- on oats; 17 U. graminis arena' on Kirleria cristaia; IS U. graminis 

 triiici on Taganrog wheat; 19 U. graminis on the leaf of barley; ,?0 U. graminis 

 on the sheath of barley ; 31 U. sorghi on corn leaf; 32 U. sorghi on corn, but with 

 teleuto stage also. 

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