64 O Journal of Mycology [Vol. 11 



about. I was unable to secure material to carry forward this 

 suggestive observation until the season following. Teleuto- 

 sporic material was obtained at Spirit Lake, Iowa, and on May 

 9, 1904, was sown on Aster ericoides, which gave very abun- 

 dant spermogonia on May 18, and strong aecidia on May 27. 

 A second sowing was made on May 13 and another on May 21, 

 which gave marked results with Aster multifiorus and A. Novae- 

 Angliae, but no infection with A. cordifolius, % A. Drummondii, 

 A. paniculatus and A. sericcus, although the host plants were 

 in vigorous growing condition. The data for these sowings are 

 as follows : 



May 9, Teleutospores sown on Aster ericoides; May 18, spermogonia ; 

 May 27, aecidia. 



May 13. Teleutospores sown on Aster multifiorus; May 23, spermogonia; 

 May 28, aecidia. 



May 13, Teleutospores sown on Aster cordifolius; no infection. 



May 21, Teleutospores sown on Aster ; May 29, spermogonia; 



June 4, aecidia. 



May 21. Teleutospores sown on Aster Novae Angliae; May 27, spermo- 

 gonia; June 8, aecidia. 



May 21, Teleutospores sown on Aster Drummondii ; no infection. 



May 21, Teleutospores sown on Aster paniculatus; no infection. 



May 21, Teleutospores sown on Aster sericeus; no infection. 



The spermogonia and aecidia of this species are wholly 

 unlike those of the common Carex rust, both in general appear- 

 and microscopic characters. The leaves of the host are 

 thickened and more or less distorted by the fungus, and the 

 aecidia have the pustular appearance of AE. recedens on Soli- 

 do go, AE. hemisphericum on Lactuca, and other Composite- 

 species having very delicate peridia, or none. The spores in- 

 stead of being a bright orange-yellow, as in most aecidia, are 

 decidedly brown. It is a very distinctive form, and yet I have 

 been unable to learn of but one collection having been made, 

 beside my own. It was found on Aster multifiorus, Bourbon 

 Co., Kans., May 29, 1902, by A. O. Garrett, who kindly sent me a 

 specimen. 



Finding the aecidium of Puccinia Stipae shows that the 

 American species is wholly distinct from the European species 

 on Stipa, which Bubak has proven by cultures belongs to an 

 aecidium on the Labiate-genus Thymus. The aecidium does not 

 attack all species of Aster alike, but judging from present cul- 

 tural results, can be expected on the suflrutescent forms hav- 

 ing coarse narrow leaves of firm texture. Such species may 

 represent a natural group within the genus, but if so the taxono- 

 mists have not defined it. It is somewhat more probable that 

 they represent an ecological group adapted to a dry atmos- 

 phere. The aecidium has not been characterized, and therefore 

 a description is appended. 



