Arthur: Cultures of Uredineae in 1908 239 



Crataegus punctata, giving a few pycnia on the first, not noticed 

 until May 4, and abundant pycnia on the last, showing April 21. 

 Both hosts matured characteristic aecia by the latter part of 

 June. 24 



15. Gymnosporangium globosum Farl., on Juniperus virgin- 

 iana L., collected by Mr. A. B. Seymour at Manchester, Mass., 

 was sown April 29 on Malus Malus, producing no infection, and 

 on Crataegus Pringlei Sarg. (seedling from tree determined by 

 Mr. W. W. Eggleston), giving abundant pycnia, and followed 

 by equally abundant aecia. Another collection made by Mr. F. D. 

 Kern and the writer at Mammoth Cave, Ky., was sown April 13, 

 on Crataegus sp., giving pycnia April 25, but nothing further, due 

 to the death of the host. 25 



16. Gymnosporangium clavipes C. & P., on Juniperus vir- 

 giniana L., collected at Mammoth Cave, Ky., by Mr. F. D. Kern 

 and the writer, was sown on two plants of Crataegus sp., April 

 13, and gave pycnia on April 25, followed by aecia by the middle 

 of June. A sowing two days later on Aronia nigra gave no in- 

 fection. 



Another collection on the same host, made by Dr. G. P. Clinton 

 at New Haven, Conn., was sown May 2 on Amelanchier erecta 

 with no infection, and on Crataegus sp., giving a few pycnia, 

 but the early maturity of the leaves checked further develop- 

 ment. 26 



17. Gymnosporangium clavariaeforme (Jacq.) DC, on 

 Juniperus Sibirica Burgsd., collected by Mr. E. Bethel at Eldorado 

 Springs, Colo., was sown April 28 on the leaves, petioles and 

 stems of Amelanchier erecta Blanch., giving pycnia May 5, and 

 aecia May 23, both in great abundance. 27 



18. Gymnosporangium Nelsoni Arth., on Juniperus scopu- 

 lorum Sarg., collected by Mr. E. Bethel at Eldorado Springs, 

 Colo., was sown May 2 on Amelanchier erecta and Sorbus ameri- 

 cana, both showing abundance of pycnia May 10. On the first 

 host no further development took place, as the plant was not vig- 



24 For previous cultures see Jour. Myc. 12! 13. 1906 \ 13* 200. 1907 ', a.nd 

 14: 17. 1908. 



25 For previous cultures see Jour. Myc. 13: 200. 1907; 14: 18. 1908. 



26 For previous cultures see Jour. Myc. 14: 18. 1908. 



27 For previous cultures see Jour. Myc. 14: 19. 1908. 



