269 CULTURES OF UREDLNEM IN i8gg [1900 



2 



j(jdhered. The spores were scraped from the host material with 

 f^L knife blade and placed on definite areas of the plant to be 

 infected, the parts marked by bits of string, and a bell jar placed 

 over the whole plant. After a day or two the bell jar was 

 removed. With most species, if the operation had been success- 

 ful, the results began to appear in six to fourteen days. 



In order that the simple procedure here outlined may uni- 

 formly give information that can be relied upon, many small 

 precautions must be observed that cannot now be spoken of. In 

 every case it is wise to first make a drop culture, to be sure that 

 the spores are viable. 



In the following outline of the work accomplished it is impos- 

 sible to go into much detail, or mention all the items of interest 

 that are naturally brought to mind. It is also impossible to 

 adjust the nomenclature in accordance with the new knowledge 

 which the cultures have furnished. 



1. Puccinia Phragmitis (Sc/ium.) Kbm. 

 The host of this species, Phragmites communis, does not grow 

 in the vicinity of Lafayette, Indiana, where the work was done, 

 and I am indebted to Dr. J. J. Davis of Racine, Wis., and 

 Professor C. E. Bessey, of Lincoln, Neb., for teleutosporic 

 material. Abundance of aecidia were obtained by sowing the 

 teleutospores upon Rumex crispus and R. obtusifolius, thus con- 

 firming the results obtained by European investigators. The 

 dates are as follows : 



May 2, Teleutospores (Wis.) sown on Rumex crispus; May J 2 spermogonia ; 

 May 15, aecidia. 



May 4, Teleutospores (Wis.) sown on Rumex obtusifolius ; May 15, spermo- 

 gonia; May 16, aecidia. 



May g, Teleutospores (Neb.) sown on Rumex crispus ; May 15, spermogonia; 

 May , aecidia. 



May 9, Teleutospores (Neb.) sown on Rumex obtusifolius ; May 15, spermo- 

 gonia ; May , aecidia. 



The preliminary drop cultures showed the most vigorous 

 germination of teleutospores obtained with any species, and far 

 surpassing most of those under observation. The sowings also 



