RvDBERG : Studies on the Rocky Mountain flora 17 



cited. Agoseris attenuata Rydb. is given as a synonym of T. 

 pubescens (Rydb.) A. Nels. A. attenuata has perfectly glabrous 

 leaves, only the involucre and the upper part of the scape being 

 villous. It would be included in Agoseris pumila (Nutt.) Rydb., 

 were it not for the decidedly acuminate inner bracts. It has very 

 little indeed to do with the decidedly pubescent A. pubescens. 



Agoseris maculata Rydb. is made a synonym of Troximon 

 villosum (Rydb.) A. Nels. It is true that they much resemble 

 each other in general habit and pubescence, but the outer bracts 

 in A. villosa are obtuse or even rounded at the apex, while those 

 of /I. wacw/a/a are abruptly and distinctly acuminate. A. villosa 

 is a plant of the lowlands of Montana, westward and northward, 

 while A. acuminata is an alpine or subalpine plant of the moun- 

 tains of Colorado. 



Troximon roseum Nutt., Agoseris agrestis Osterhout, and A. 

 roseata Rydberg are made synonyms of Troximon glaucum. I 

 have not seen the type of T. roseum Nutt., but, as I interpret it, 

 it is a plant closely related to T. laciniatum Nutt., not to T. 

 glaucum. Agoseris agrestis Osterhout is related to A. glauca, but 

 if made a synonym of anything it should be of Troximon pumilum 

 Nuttall, having the same pubescent involucral bracts, but the 

 leaves are pinnatifid and caudate-acuminate instead of entire and 

 obtuse or rounded at the apex. 



Under Troximon glaucum dasycephalum Professor Nelson gives 

 a citation from Piper's Flora of Washington: "This plant differs 

 from T. glaucum only in having a pubescent involucre. It is 

 scarcely worth nomenclatural recognition." I think that both 

 Piper and Nelson are incorrect in this statement. In Agoseris 

 glauca (Nutt.) Greene the involucre is decidedly obconic, and 

 the leaves narrowly oblanceolate or linear and glaucous; in Agoseris 

 scorzoneraefolia (Schrad.) Greene (Troximon glaucum dasycepha- 

 lum T. & G.) the involucre is decidedly campanulate, sometimes in 

 age almost hemispheric, the outer bracts and the leaves broader, 

 and the latter scarcely glabrous. Those who have access to the 

 Botanical Magazine may compare plate 1667 Q.nd plate 3462, which 

 give good illustrations of Agoseris glauca and A. scorzoneraefolia 

 respectively. 



Under Troximon glaucum dasycephalum, Agoser.s altissima is 



