Explanation of Plate IV. 



52a. Uromvces acuminatus Arth. 



On Spartina cy710snroid.es (L. ) Willd., from Iowa. 

 Five uredospores and one teleutospore. 



52^. Uromyces acuminatus, Atth. 



On Spartina cynosuroides (L.) Willd., from Iowa. 

 Nine telentospores; a slender form. 



52r. Uromyces acuminatus Arth. 



On Spartina cynosuroides (L. ) Willd., from Iowa. 

 One uredospore and six teleutospores. 



52^. Uromyces acuminatus Arth. 



On Spartina cynosuroides (L.) Willd., from North Dakota. 

 One uredospore and seven teleutospores. 



53<2. PUCCINIA SEYMOURIANA Arth. 



On Spartina cynosuroides (L. ) Willd., from Wisconsin. 

 Six uredospores and four teleutospores. 



