410 



are placed lOgether under this (Hil' .ijciicral "catcli all" name, which has no 

 particular signifioanee. Field observations and cultures, aloni,' with further 

 microscopical work, are necessary to segregate these forms. No doubt som.; 

 of them will be found to belong with aecial forms ah'eady connected, 

 while others of these forms will doubtless be found to have new heteroe- 

 cious connections.) 



On CARDUACEAE: 



Colcosanthus grand iflorns (Hook.) Kuntze (BrickcUia gnindiflora 

 Hook.), New Mexico. 



Vhrysoyonum virgiiiiaiiKiii ilcntatiiin A. (hay, Disti'ict of Columbia. 



Chrysothumnus Parnjl (A. Gray) Greene {Aplopapinis I'arrtji A. Gray) 

 New Mexico. 



Dugahliu Hoopsii (A. Gray) liydb. {Ileloiiuni lluopxii A. Gray), Col- 

 orado. 



Ilelenium autumnale L., Colorado. 



Polymnia canadensis L., Iowa, Wisconsin. 



Rudbeckia hirta L., Nebraska. 



Rudheckia laciniata L., Iowa, Nebraska, Wisconsin, Wyoming. 



Rudhcckia trilaha L., Delaware. 



ACIvXUWLEDG MENTS. 



The writer wishes here to express his sincerest thanks to all who have 

 assisted in any way in the pursuance of this study. The kindly attention 

 and critical suggestions of Dr. J. C. Arthur, under whose direction the 

 work has been done, has been greatly ai)preciated throughout. Acknowl- 

 edgments are especially due Dr. Arthur U>v the free use of his exceptinn- 

 ally large private collection of plant rusts, as well as for free access to 

 his extensive private library on this sub.1ect, without either of which this 

 study would not have been i)ossible at this time. Free use was also made 

 of his private card indices and manuscri])t sheets on the subject, which 

 very greatly facilitated the use of both the library and the herbarium, and 

 where much iid'ormation was already brouglit together in available form. 



Sincere; (hanks are also extended to the other members of the botan- 

 ical department of the Indiana ]'l\])erinient Station, viz: to Dr. I'rank D. 

 Kern, .Mr. C. It. Orion, Miss lOvelyn Allison and Miss Mary .\. Fitch, for 

 kindly assistance in vai-ions ways. 



