Arthur: Cultures of Uredineae in 1910 13 



20. Uromyces Sporoboli E. & E., on Sporoholus neglectus 

 Nash, collected by Dr. E. W. Olive, at Brookings, S. D., was 

 sown on Lepargyraea canadensis, Elaeagnus angustifolia, Amor- 

 pha nana, Erigeron annuus (on two different dates), and Arnica 

 sp., with no infection. 



21. Aecidium on Euphorbia commutata Engelm. was obtained 

 in the vicinity of Lafayette, Ind., by Messrs. F. D. Kern and T. 

 Billings. The living plants were placed in pots and continued to 

 flourish. They bore aecia in all stages of maturity. These plants 

 were adjusted in a moist chamber over the following hosts, so 

 that aeciospores fell spontaneously upon the young leaves : Astra- 

 galus canadensis, Pisum sativum, Lathyrus palustris, Medicago 

 sativa, and Trifolium pratense. No infection was obtained. 



Successful cultures supplementing previous work. — The 

 facts derived by growing the following species of rusts supple- 

 ment those obtained from previous cultures in this series or from 

 cultures recorded by other American or European investigators. 



I. PucciNiA Grossulariae (Schum.) Lagerh., on Carex tenuis 

 Rudge, collected at Pictou, Nova Scotia, by Professor W. P. 

 Eraser, was sown April 7 on Erigeron annuus, Solidago cana- 

 densis. Aster paniculatus and Ribes Cynosbati, with infection only 

 on the last,^* showing pycnia April 16, and aecia April 25. Simi- 

 lar material obtained by the writer at Isle au Haute, Me., was 

 sown on the same hosts, but omitting Erigeron, and with similar 

 results. 



A collection on Carex pallescens L., made by Professor W. P. 

 Eraser at Pictou, Nova Scotia, the previous fall, was sown April 

 8 on Erigeron annuus, Solidago canadensis, Aster paniculatus 

 and Ribes Cynosbati, with infection only on the last, showing 

 abundant pycnia April 16, and aecia April 22. A similar collec- 

 tion, made by Prof. Eraser in the spring, wias sown April 18, 

 without infection, on Lysimachia terrestris, Lactuca scariola, 

 Rudbeckia laciniata, Polygala Senega and Apocynum cannabinum. 

 Two days earlier it was sown on Ribes Cynosbati, resulting in 

 good infection, showing pycnia April 27, and aecia May 3. 



See Bot. Gaz. 35: 11. 1903. 

 "For similar negative results see Mycol, 2: 218'. 1910. 



