Cultures of Uredineae in 1916 and 1917 



299 



6, was sown on Berberis vulgaris on April 23, and began to show 

 pycnia April 30, and aecia May 4. 6 



3. Puccinia Rhamni (Pers.) Wettst. — A collection made by 

 Mr. G. B. Posey in December, 191 5, at Corvallis, Oregon, on 

 Agrostis sp., was sown May 11, 011 Rhamnus Purshiana, and 

 showed pycnia in fair numbers May 20, but made no further de- 

 velopment, although the leaves remained healthy and in good 

 growing condition for a considerable time. 



4. Puccinia Distichlidis Ellis & Ev. — This rust was found 

 May 24 by Mr. Geo. E. Osterhout and the writer in great 

 abundance on over-wintered Spartina Michauxiana in a field at 

 Windsor, Colo., and entirely unmixed with any other rust known 

 to occur on the same host. The spores had not yet germinated. 

 Large groups of Steironema ciliatum nearby, the supposed alter- 

 nate host, were already six or eight inches high and free from 

 infection. The teliospores were sown on S. ciliatum in the 

 greenhouse at Lafayette on May 30, and gave a heavy infection, 

 showing pycnia June 4, and numerous aecia June 10. This result 

 confirms the work of 191 5 7 and establishes the life cycle of the 

 species beyond doubt. On June 12 Mr. Osterhout sent a fine 

 collection of aecia on 6\ ciliatum from the place where the cul- 

 tural material had been obtained, being the second field collection 

 for the species, the previous one being made in North Dakota. 



5. Puccinia Muhlenbergiae Arth. & Holw. (P. Schedon- 

 nardi K. & S.)« — Telial material of this rust was found May 28 

 by Professor H. S. Jackson and Mr. E. Bethel, on Muhlen- 

 bergia gracillima, a low, tufted and fine leaved species growing 

 on the arid plains near Pueblo, Colo., associated with Mahastrum 

 coccineum, suspected of being an alternate host. A sowing was 

 made on M. coccineum June 2, which gave pycnia June 18, and 

 aecia June 25, both in strong development. 



Telial material of Puccinia Schedonnardi, on Schedonnardus 

 paniculatus was obtained by Mr. Bethel, Professor Jackson and 

 the writer at Pueblo, Colo. After the preceding trial showed 

 signs of success, a striking resemblance was noticed between the 



6 For previous cultures see Jour. Myc. 8: 53. 1902; n\- 57. 1905; 12: 17. 

 1906; 13: 198. 1907; 14: 16. 1908; Mycol. 2: 227. 1910; and 4: 18. 1912. 



7 See Mycol. 8 : 136. 1916. 



