RYDBERG: Rocky MouNTAIN FLORA 325 
almost equally floccose on both sides with loose, not dense tomen- 
tum, sometimes slightly glandular; inflorescence large, corym- 
bosely paniculate; heads somewhat conglomerate at the ends of 
the branchlets; involucre hemispheric or nearly so, 6 mm. high, 
only slightly tomentose at the base; bracts broadly ovate, acute 
light straw-colored or white; achenes glabrous; pappus_ straw- 
colored. 
This species is intermediate between Guaphalium microcepha- 
lum and G. decurrens; perhaps more closely related to the latter, 
of which it has the general habit and the larger nearly hemispher- 
ical involucres, but the leaves are nearly as tomentose above as 
beneath. They are slightly if at all glandular; the stem is not 
at all so. The pubescence is that of G. microcebhalum but the 
inflorescence is more open and inclined to be flat-topped and both 
the involucre and its bracts are much broader. 
Montana: Columbia Falls, Aug. 11, 1894, R. S. Williams 
(type, in herb. N. Y. Bot. Gard.); woods, Belton, Aug. 25, 1903, 
Umbach 752. 
NacreA A. Nels. 
I believe that this genus is based on the essentially staminate 
plant of Anaphalis. There is a duplicate of the type of Nacrea 
lanata in the herbarium of the New York Botanical Garden, but 
the specimens are so young that the real structure of the flowers 
can not be made out. It may be that Nelson had better developed 
material on hand. The expressions “‘akenes (immature in these 
specimens)”’ indicate, however, that he did not have developed 
fruit. The so-called staminate flowers of Anaphalis are in reality 
hermaphrodite flowers with sterile pistils. (See Bentham & 
Hooker, Genera Plantarum.) The styles in them are undivided 
and the achenes remain undeveloped. In the description of Nacrea 
there is nothing said about the styles being undivided or 2-cleft. 
In the herbarium of the New York Botanical Garden there are 
two specimens collected in the Big Horn Mountains, one by T. A. 
Williams in 1898, and the other by Dr. H. Hapeman in 1892, 
which (especially the first mentioned) are so close in every respect 
to the duplicate of the type of Nacrea lanata, that anybody would 
take them for the same species. They are better developed and 
belong without doubt to an Anaphalis. Whether they can be 
separated specifically from A. subalpina is doubtful. 
