Jan. 190 b] 
Cultures of Uredineae in 1905 
11 
ter. Doubtless then the Rust of Maize is carried over from year 
to year in part by means of surviving uredospores. Finally, it 
may be said that while this interpretation was, of course, not 
unthought of by uredinists, I preferred myself to record the final 
judgment only after further work had been carried on in my own 
experimental laboratory. Therefore this is the conclusion of the 
whole matter. 
CULTURES OF UREDINEAE IN 1905. 1 
BY J. C. ARTHUR. 
The present article forms the sixth of a series of reports 2 
by the author upon the culture of plant rusts. They cover the 
years from 1899 to the present year, inclusive. In these studies 
the grass and sedge rusts hold a prominent place, but other hete- 
roecious and autoecious species have been included, and during 
the present season the work has been extended to the so-called 
opis, micro and lepto forms, and also to species with amphi- 
spores. 
The cooperative agreement between the Bureau of Plant 
Industry of the U. S. Department of Agriculture and the Indiana 
Experiment Station, which existed for carrying on the culture 
work in the spring of 1904, was again established, extending 
from July, 1904, to April 30, 1905, making it possible to have 
an assistant during this period, who devoted nearly his whole 
time to the study of the rusts. The position was first held by 
Mr. J. C. Marquis, who was succeeded on October 1, 1905, by 
Mr. Frank D. Kern, and after the expiration of the cooperative 
agreement Mr. Kern was retained by the Experiment Station to 
continue the work. After May 10 all the work fell upon Mr. 
Kern until September, covering the most important part of the 
culture period, the author being absent in Europe. It could not, 
however, have been entrusted to better hands, as the fine ability 
displayed in the work during the previous season, coupled with 
considerable experience already acquired, enabled him to meet 
the new conditions as they arose, and the judgment and caution 
indispensable in securing authoritative results. 
Much of the completeness of the work is due to the kindly 
assistance of correspondents, who have sent teleutosporic mate¬ 
rial, and especially to Messrs. E. Bethel, Denver, Colo.; J. M. 
Bates, Red Cloud, Neb.; A. O. Garrett, Salt Lake City, Utah; 
1 Read before the Botanical Society of America at the New Orleans 
meeting, January 1, 1906. 
2 See Bot. Gaz. 29 : 268-276: Jour. Mycol. 5:51-56; Bot. Gaz. 35 : 
10-23; Jour. Mycol. 10 : 8-21 and 11 : 50-67. 
