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4 



Nelson: New Plants from Wyoming. 35T 



Nacrea 



Perennial from horizontal rootstocks : stems stoutish, erect, 

 permanently lanate as are also the leaves : heads discoid, congested 

 in a cymose corymb : involucral bracts thin, pearly white, plun- 

 serially imbricated: flowers all hermaphrodite: pappus bristles 

 capillary, thickened at the apex : corolla inserted below the sum- 

 mit of the akene which projects into the tube of the corolla as a 

 short cylindrical base supporting the style : akene constricted at the 

 point'where the corolla is inserted, basal portion (akene proper ?) 

 obconical : receptacle plane, alveolate. Name in allusion to the 

 pearly-white involucral bracts. 



Nacrea lanata 



Rootstocks long, slender, giving rise to numerous fibrous 

 roots : stems singly from the crowns, very strict, leafy, 2-4 dm. 

 hi'-h • leaves (like the stem) densely white lanate, thick, rather 

 n<?id erect or somewhat apprcssed to the stem, sessile or clasping, 

 alt nearly similar, narrowly oblong, the rounded-tapering apex 

 sub-acute, 4-8 cm. long, the floral much reduced : heads about 

 6 mm. high, bracts wanting except for a few foliar ones at the 

 lower pedicels : involucral bracts from ovate to narrowly obovate, 

 the inner ones with a narrowed base : corolla tube slender, the 

 limb slightly expanded, yellow: pappus bristles barbellulate the 

 unicellular barbules becoming large and obtuse toward the thick- 

 ened apex of the bristle : akenes (immature in these specimens) 

 roughened with upwardly pointed papillae. 



After holding this plant for more than two years without find- 

 ing a genus for it, I now propose the above to receive it. Its ap- 

 pearance suggests Anaphalis but the floral characters exclude it 

 from not only that, but, as at present characterized, fi'om the sec- 

 tion Gnaphaheac. I think, however, that the limits of that section 

 must be so enlarged as to admit this genus next to Anaphalis. 

 This plant was collected at a sub-alpine station in the Rig Horn 

 mountains, on Little Goose creek, in 1896, July 18. Type speci- 

 men in Herbarium University of Wyoming, no. 2391. 



Gnaphalium angustifolium 



Low annual, branching from the base, the two to several slen- 

 der stems decumbent-spreading or assurgent, 8-12 cm^ long, 

 loosely floccose on the stems and involucres, appressed pubescent 

 on the leaves : leaves numerous, from narrowly to broadly linear, 

 o-^ cm long, the floral leaves not reduced and bract-like : the 



