193 



24 JL+JtJ Mycologia 



identical with the widespread Astragalus rust. The species is one 

 that does not readily produce teliospores. 



24. Uromyces Medicaginis Pass., on Medicago sativa L., was 

 sent by Mr. H. S.. Coe, from Ames, Iowa. Urediniospores were 

 sown September 26, on Medicago sativa in the greenhouse, and 

 uredinia began to appear October 8. On November 14, uredinia 

 from this culture were sown on Medicago sativa, Trifolium pra- 

 tense, T. medium, and T. repens, giving uredinia on the first 

 December 3, but with no infection of the Trifolium plants. 



The aecia of Medicago rusts are not definitely known. In 

 Europe a form usually assumed to be the same occurs on Trifo- 

 lium pratense, and this was made by Schroter to infect Euphorbia 

 Cyparissias. This form has not been detected in America. The 

 present culture seems to show that the Medicago rust will not 

 pass over to Trifolium, at least by means of urediniospores. 



25. Gymnosporangium Juniperi-virginianae Schw., on Ju- 

 niperus virginiana L., collected by Dr. F. D. Kern in the vicinity 

 of Lafayette, Ind., was sown April 7, on Malus Mains, giving 

 numerous pycnia April 19, but the leaves matured before aecia 

 were formed. 39 



26. Gymnosporangium clavipes C. & P., on Juniperus sibirica 

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

 sown May 3, on Amelanchier erecta and Crataegus tomentosa, 

 giving numerous pycnia on both hosts May 16, and equally 

 numerous aecia June 6, for the first host and June 11, for the 

 second. 



Aecia from this culture on Amelanchier erecta were used to 

 sow June 7, on a small plant of Juniperus sibirica, and many 

 finely developed telia appeared in May 191 1, the exact date not 

 recorded. 40 



These cultures are interesting in showing that the telia mature 

 in the spring following infection, and do not require an additional 

 year as some other species of Gymnosporangium do. 



27. Gymnosporangium clavariaeforme (Jacq.) DC., on Juni- 



39 For previous cultures see Jour. Myc. 12: 13. 1906; 13: 200. 1907; 14: 17. 

 1908 ; and Mycol. 1 : 238. 1909. 



40 For previous cultures see Jour. Myc. 14: 18. 1908; Mycol. 1: 239. 1909; 

 and 2 : 229. 1910. 



