CONTRIBUTIONS FROM THE ROCKY MOUNTAIN 
HERBARIUM. 
AVEN NELSON. 
To THOSE who have known them in the field and who have 
studied them carefully in the herbarium, desert plants are of 
peculiar interest. No other plants show so many adaptations to 
their environment and, as a consequence, so many variant 
characters that have become fixed. During the spring of 1902 
Mr. Leslie N. Goodding, a student in the University of Wyoming, 
was sent into the field in the interest of the Rocky Mountain 
Herbarium. He made collections in southern Nevada, southern 
Utah, the Wasatch Mountains, and in the Uintah Mountains, 
especially on their southern desert slopes. He secured many 
rare species of great interest, as well as some novelties. This 
paper is based, in a large measure, upon his field work. 
NEW GENERA AMONG THE APLOPAPPUS SEGREGATES. 
Notwithstanding the attention that the genus Aplopappus Cass. 
has had in recent years, it seems that further division would tend 
to simplicity. The genus Stenotus as now constituted is nearly 
homogeneous. Before the recent separation of two of the species 
and their erection into the genus Stenotopsis by Rydberg (Bull. 
Torr. Bot. Club 27: 617), a concise generic description was 
unthinkable. My attention was called to this fact recently when 
some material of Stenotus interior (Coville) Greene came into my 
hands for determination. To one perfectly familiar with the 
normal species, the possibility that this plant also was listed as 
a Stenotus did not for some time occur to me. Several other 
genera come to mind more readily than this, among them 
Macronema, when one has in hand only the leafy floriferous 
twigs that constitute the usual herbarium specimens. 
The difficulties encountered in generically placing the original 
species of the group (Aplopappus linearifolius DC.) has been 
recognized from DeCandolle down. Greene has stated the 
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