Arthur: Cultures of Uredineae in 1909 229 



first showing June 12. The leaves matured so rapidly that no 

 aecia were formed. A sowing at the same date on Viola prinnili- 

 folia gave no infection. This species of rust has been grown 

 upon Viola by Dr. John L. Sheldon,-'^ but previous attempts made 

 in my own laboratory have failed.-" The reason for the failures 

 seems to be the tardiness in making the cultures, by which the 

 violet leaves are too mature and ripen so rapidly that infection is 

 not secured. I am indebted to Dr. Sheldon for the suggestions, 

 field observations and culture material, which have enabled me 

 to add this species to the list of completed life cycles. 



15. Uromyces Spartinae Farl., on Spartina cynosiir aides 

 Willd. collected at Kulm, N. D., by Dr. J. F. Brenckle, was 

 sown April 23 on Lysimachia qiiadrifolia, with no infection, and 

 at the same date on Steironcnia ciliatuni and S. lance olatiim, giv- 

 ing rise to pycnia May 5 on the former and May 8 on the latter. 

 In both cases growth did not extend to the formation of aecia 

 owing to the feeble condition of the host plants.-^ The confusion 

 of this species of rust with Uromyces acmninafus Arth. has 

 already been discussed above among unsuccessful cultures. 



16. Gymnosporangium globosum Farl., on Jiiniperus virgin- 

 iana L., collected at Asheville, N. C, by Mr. F. D. Kern, was 

 sown May 15 on Mains loensis, Crataegus punctata and C. coc- 

 cvnea, with no infection on the first and second, but on the last 

 giving rise to pycnia May 25 in abundance, followed by aecia 

 which were mature July 26P 



17. Gymnosporangium clavipes C. & P., on Juniperus sibi- 

 rica Burgsd., collected at Leland, Mich., by Mr. F. D. Kern, was 

 sown June 5 on the fruit of Ainelanchier erecta, giving rise to 

 pycnia June 14, and to mature aecia August 3, both in abundance. 

 At the same time it was sown on the leaves of Crataegus punctata, 

 giving rise to numerous pycnia, but as the plant was not well 

 established further development was soon checked. There ap- 



^® Torreya 9 : 55. 1909. 



^ See Mycol. i : 232. 1909. 



For previous cultures see Jour. Myc. 12: 24. 1906; and 14: 17. 1908, 

 under the name U. acnminatns. 



^® For previous cultures see Jour. Myc. 13: 200. 1907; 14: 18. 1908; and 

 Mycol. I : 239. 1909. 



For previous cultures see Jour. Myc 14: 18. 1908; and Mycol. i: 239. 



1909. 



