47 



was collected on wormwood (Artimesia biettmti), where it was 

 equally injurious, when found in sufficient quantities. 



PERISPOEIACEAE. THE BLIGHTS. 



EUYSIPHI: ci< HOEACEARUM, DC. On great rag weed (Ambrosia 

 trifida,} and golden rod (tiolhlayo .^>/>.). Common and often 

 quite destructive. 



UKDEINEAE. THE RUSTS. 



I'uo.MYCKs EuriiORKiAE, Cke. <fe Pk. Bust of Euphorbia or spurge. 

 II III on leaves of spurge (Euphorbia serpyllifolia and E. 

 hypericifolia). One of our commonest rusts. It seldom be- 

 comes very destructive. 



UROMYCES POLYGONI, (Pers.) FuckeL I II III. On leaves 

 and stems of knotweed, or door weed (Polyyonum erection, I*. 

 (t vie f flare and P. ramosissimum). A very commons pecies often 

 becoming quite destructive in all its stages. May Septem- 

 ber. 



UROMYCES BUDHECKIAE, Arthur & Holw. Cone nower rust. Ill . 

 On cone flower ( Rudbeckia laciniatd). Forms definite raised, 

 light brow r n, or brown, spots on the underside of the leaf. 

 The tissues of the affected spot, after a time, fall away, leav- 

 ing an irregular hole- When the whole leaf is affected, it 

 rolls up and falls off. A common and destructive species. 

 June October. 



PUCCINIA coNvoLvuLi, (Pers.) Cast. Morning glory rust II III. 

 On leaves of wild morning glory, or hedge bind-weed ((Jon,- 

 volvulits sepium). A common and often very injurious species, 

 often destroying nearly every leaf. 



PUCCINIA EMACULATA, Schw. III. On old witch grass (Pani- 

 t-H.in capillare). Usually on the upper surface of the leaves, 

 causing them to shrivel and dry up. Not uncommon, and 

 frequently destructive. 



PUOCINIA IIELIANTIII, Schw. Sunflower rust. II & III. On sun- 

 flower (Helianthus annuns^ M< mawimiliam, & H. gigant^us] 



