162 



Arthur: Cultures op I redinbae in 19091 o 22* 



dioicum, Aetata alba, Caulaphyllum thaUctroides, Boehmeria cy- 

 Kndrica, Myosotis palnstris, Mimulus ringens, Polemonium refh 

 tans, Hydrophyllum virginicum, Poly gala Senega, Dirca palus- 

 tris, Psoralea Onobrychis and Ipomoea pandurata. 



Aeciospores from Impatiens aurea Muh!., were sown on three 

 specie^ of Blymus. For this purpose small plants bearing aecia 

 were taken from the field, where they grew close together, and 

 had presumably received infection from one source. These were 

 established in pots, and the pots adjusted over the plants of 

 Elytnus to be infected, so the spores would drop of themselves 

 upon the leaves of the grass, bell jars being used as usual to secure 

 the right degree of moisture for the germination of the spores. 

 In this manner aeciospores were sown June 4 upon Elytnus vir- 

 ginicus L., E. canadensis L. and E. striatus Willd. In all three 

 cases uredinia began to show June 17, and continued to increase 

 for some time, but the conditions were not such as to keep the 

 plants in healthy condition for the maturing of telia. 



Former cultures- 4 had demonstrated the genetic connection be- 



! the aecia on Impatiens and telia on Elymus virginicus. 



The present season's work indicates that the rust on all species of 



Ely inns in the region east of the Rocky Mountains belongs to one 



species, Pnccinia I nipaticntis. 



12. PucciNiA POCULIFORMIS (Jacq.) Wettst., on Agropyron 

 pseudorepens Scribn. & Sm., collected at Kulm, N. D., by Dr. J. F. 

 Brenckle. was sown May 4 on Berbcris vulgaris, giving rise to 

 pyenia May 12, and numerous aecia May 24. Another collection 

 on Sitanion I ongi folium J. G. Sm., made at Tolland, Colo., 9,000 

 feet altitude, by Mr. E. Bethel, was sowm May 17 on Bcrberis 

 vulgaris, and gave pyenia May 29, but owing to maturity of the 

 leaves did not reach the production of aecia. Still another collec- 

 tion on Sitanion longifolinm, made at Eldorado Springs, Colo., 

 4,500 feet altitude, by Mr. E. Bethel, was sown April 26 on Bet" 

 bcris vulgaris, and gave pyenia May 3, and aecia May 12, 

 both in great abundance. On May 17 the barberry plant bear- 

 ing aecia, produced in the last culture, was arranged over a 

 pot in which young wheat plants | Triticum vulgare Vill. ) were 

 growing, in such a manner that the aeciospores could fall 



- 4 See Bot. Gaz. 35: 18. 1903: Jour. Myc. 10: 11. 1904: and 11: 57. 1905. 



