Arthur: Cultures of Uredineae in 1910 



25 



perus sibirica Burgsd., was sent by Mr. E. Bethel, from Boulder, 

 Colo., and sown April 7, on the young fruit of Pyrus communis, 

 which fell off before time for infection to show, and also on the 

 leaves of Amclanchier ere eta and Crataegus punctata. On the 

 Crataegus a few pycnia showed April 15, but no aecia developed. 

 On the Amelanchier numerous pycnia appeared April 13, and 

 many aecia April 25.*^ 



28. Gymnosporangium nidus-avis Thaxt., on Juniperus vir- 

 giniana L., was sent from Washington, D. C, by Dr. Haven 

 Metcalf, and sown April 16, on leaves of Cydonia vulgaris, giving 

 a few pycnia May 2, and also on the young fruit of Amelanchier 

 vulgaris, giving a few pycnia first noticed May 24. In both 

 instances no further development occurred. 



29. Gymnosporangium cornutum (Pers.) Arth., on Juni- 

 perus sibirica Burgsd., sent from Palmer Lake, Colo., by Mr. E. 

 Bethel, was sown May 18 on Sorbus americana, Aronia arbuti- 

 folia, and Amelanchier erect a. Infection was secured only on the 

 Sorbus, the pycnia being produced in abundance but tardily, and 

 the date was not taken. The plant did not thrive, and no aecia 

 matured, although on August 16 they were showing.*^ 



30. Gymnosporangium Davisii Kern, on Juniperus sibirica 

 Burgsd., sent by Dr. J. J. Davis from Wind Lake, Wis., was sown 

 May 3, on Aronia arbutifolia, A. nigra, Sorbus americana, Ame- 

 lanchier erecta and Crataegus tomentosa, without results. Another 

 sowing was made May 12, on the two species of Aronia, which 

 resulted in a few pycnia on A. nigra, showing May 27. Still 

 another sowing on A. arbutifolia was made May 18, and gave a 

 few pycnia May 25. In neither instance did aecia develop.** It 

 is probable that the conditions under which the cultures are made 

 in the greenhouse are not favorable for this rust. 



31. Gymnosporangium Betheli Kern, on Juniperus scopu- 

 lorum Sarg., sent by Mr. E. Bethel from Boulder, Colo., was sown 



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



1909. 



*- For previovis cultures see Jour. Myc. 14: 19. 1908; and Mycol. 2: 230. 

 1910. 



*^ For previous cultures see Mycol. i: 240. 1909; and 2: 230. 1910. 

 For previous cultures see Mycol. i: 241. 1909, where an error was made 

 in assuming that this species occurs in Europe; see also Mycol. 2: 216. 1910. 



