** y r A k^ I 



Studies on the Rocky Mountain Flora.— I* 



By p. a. Rydberg 



(With Pi axes 5 and 6.) 



SPECIES OF 8ENECI0 OF THE LOBATUS, AUREUS, 8UBNUDUS AND T0MENT08U8 GROUPS 



It may seem strange that I present here a paper on Senecio, 

 when it is well known to me that Mr. Greenman is occupied in 

 preparing a monograph of the genus in all North America, from 

 the arctic regions to the Isthmus. My work was begun a year ago, 

 and before I knew of Mr. Greenman's work. I have not been able 

 to present my results in print before now, and I do it with the 

 good will of the gentleman mentioned, and with the understanding 

 that I confine myself to the Rocky Mountain region. 



The four groups treated here are closely related and grade 

 into each other. They might have been treated as a single 

 group but even this would have been more or less artificial and 

 ill-defined, because there are several intergradations with related 

 groups. The more foliose species of the Aurei as ^. platylobiis 

 and ^^ Idahoensis described below connect with the Eremophili ; 

 5". cyiiibalarioidcs with the Alpicolae, and 6". cajwvirens with the 

 Cani. 



The work presented here is based on my own studies in the 

 field and the specimens found in the herbaria of the New York 

 Botanical Garden, Columbia University and College of Pharmacy, 

 all in New York City. 



LOBATI 



Annuals or biennials or perennials with a taproot, perfectly 

 glabrous in age or slightly floccose at the bases of the leaves, more 

 or less leafy throughout, 3 dm. or more high : leaves, all except 



*The author intends to publish under this title a series of papers on the Botany of the 

 Rocky Mountain Region. The intention is not however to Hmit these studies to the 

 botany of the mountains proper, but will include also the Great Plains to the eastward. 

 They will comprise the following states and territories : eastern British Columbia, Alberta. 

 Saskatchewan, Assiniboia, Montana, Idaho, Wyoming, Colorado, New Mexico, east- 

 ern Utah, and the extreme western portions of the Dakotas, of Nebraska, Kansas, Okla- 

 homa and Texas. 



(169) 



