THE HETEROECISM OF PUCCINIA MONTA- 

 NENSIS, P. KOELERIAE, AND 

 P. APOCRYPTA 1 



E. B. Mains 

 (With Text Figures 1-4) 



Puccinia montanensis Ellis, P. Koclcriae Arth., and P. apocrypta 

 Ellis & Tracy belong to the group of grass rusts having long- 

 covered telia to which P. triticina Erikss. and P. sccalina Grove 

 (P. dispersa Erikss.) belong. In connection with the investigation 

 of the last-named rusts, which is being conducted by this laboratory 

 in cooperation with the Office of Cereal Investigations of the U. S. 

 Department of Agriculture, some attention has been given to a 

 study of the related rusts of this group as a part of the general 

 rust investigations of the laboratory, for the help which such a 

 study will afford in the solution of cereal rust problems. In con- 

 nection with this work considerable taxonomic study of the mate- 

 rial in the Arthur herbarium has been necessary, which has re- 

 sulted in a partial realignment of the rusts involved and has formed 

 the basis for the treatment of these as finally published in the 

 North American Flora. 2 



Puccinia montanensis 



Of the three rusts Puccinia montanensis is perhaps the most dis- 

 tinctive. It was described by Ellis 3 from a collection upon Elymus 



1 Contribution from the Botanical Department of the Purdue University 

 Agricultural Experiment Station. This work is in part a result of the studies 

 being conducted cooperatively between that Department and the Office of Ce- 

 real Investigation, Bureau of Plant Industry, U. S. Department of Agriculture. 



Read before the Mycological Section of the Botanical Society of America 

 at Chicago, 111., on Dec. 29, 1920.' 



2 Arthur, J. C, & Fromme, F. D. Dicaeoma on Poaceae. North Ameri- 

 can Flora 7: 325, 330 and 332. 1920. 



3 Ellis, J. B. Descriptions of Some New Species of Fungi. Journ. Mycol. 

 1: 274. 1893. 



315 



