Jan. 1908] Cultures of Uredineae in 1907 -^ U O 17 



any morphological distinctions exist is yet uncertain, but none has 

 yet been detected. 



13. Uromyces acuminata Arth. Teliosporic material on 

 Spartina cynosuroides Willd., collected at St. Paul, Neb., by 

 Rev. J. M. Bates, was sown twice on thrifty plants of Lysima- 

 chia quadrifolia, with no infection. It was sown on Steironcma 

 ciliata May 14, giving rise to strongly developed pycnia May 

 22, and aecia May 2j ; while a second sowing May 30, gave pyc- 

 nia June 6, and aecia June n. 20 



These results confirm the studies of previous seasons, show- 

 ing that the rust called by this name in different sections of the 

 country should be segregated into distinct species, or else into 

 physiological species. More observations and material for cul- 

 tures are required from all parts of the region east of the Mis- 

 sissippi river. 



14. Uromyces Scirpi (Cast.) Burr. Teliosporic material 

 on Scirpus fluviatilis (Torr.) A. Gray, collected at St. Paul, Neb., 

 by Rev. J. M. Bates, was sown on Oxypolis rigidus, with no in- 

 fection. It was sown on Cicuta maculata May 3, giving rise to 

 abundant pycnia May 13, and aecia May 20, thus confirming the 

 work of last season. 21 



15. Uromyces Silphi (Syd.) Arth. Teliosporic material 

 on J uncus tenuis Willd., collected at Red Cloud, Neb., by Rev. 

 J. M. Bates, was sown on Silphium perfoliatum April 23, giving 

 rise to pycnia May 4, and aecia May 11. Similar material sent 

 by the same collector from Grand Island, Neb., was sown on an- 

 other plant of the same host May 31, giving rise as before to 

 pycnia June 12, and aecia June 17. These results well confirm 

 the work of last year. 22 



16. Phragmidium speciosum Fr. Teliosporic material on 

 Rosa pratincola Greene (same as previously reported under the 

 name R. Arkansana) , collected in a meadow at Eldorado Springs 

 (Boulder county), Colo., by the writer, was sown on Rosa pra- 

 tincola May 20, giving rise to pycnia May 27, and aecia June I. 23 



17. Gymnosporangium Juniperi - Virginianae Schw. 

 Teliosporic material on Juniperus Virginiana L., collected at 

 Dayton, Ind., by Mr. F. D. Kern, was sown on Crataegus punc- 

 tata, with no infection, and on a cultivated apple, Malus Malus, 



20 For previous successful and unsuccessful cultures see Jour. Myc. 

 12.24. 1906; 13 :193. 1907. 



21 For previous cultures and discussion see Tour. Myc. 1^:199. 1907. 



22 For previous cultures see Jour. Myc. 13 :202. 1907. 



18 For previous cultures see Bot. Gaz. 35:17. 1903; Jour. Myc. jt:53. 

 1905. 



