CATALOGUE. 
193 
363. Scurfy-pubescent and mealy ; leaves broadly triangular, the lower ones 
somewhat reniform, irregularly dentate, 3-6" long and broad ; heads axillary 
or subcorymbose, at length nodding ; involucral scales in two rows, 5 outer 
subfoliaceous lanceolate and persistent, and 12-15 inner scarious 2-4-nerved 
deciduous ones ; corolla very slender, the apex pubescent with a few long 
crisped webby hairs ; achenia very villous, the hairs rather rigid and often 
slightly bifid at the extremity. — A low branching whitish herb, with the look 
of Ohione nrgentea. New Mexico to California ; Humboldt Plains, Nevada, 
(Torrey.) Carson Desert, and near Hot Springs in the Hot Spring Mount- 
ains, Nevada; 4-4,500 feet elevation; July, August. (680.) 
Tetradymia^ canescens, DC. Densely white-tomentose ; leaves linear, 
6-12" long and about 1" wide, rigid, mucronate, but not spinescent, axillary 
fascicles of smaller leaves none ; heads racemose-corymbed ; involucre 5-6" 
long, of 4 oblong obtuse carinate scales ; florets 4 ; achenia sparingly villous 
with soft short hairs, soon becoming nearly smooth.-: — Shrubby, forming a 
densely branched bush 1-3° high, the main stem often 2' thick at the bas.c. 
The same habit is common to all the genus. — British Columbia, Oregon and 
California ; Mt. Davidson, (Bloomer.) Virginia, Truckee and East Humboldt 
Mountains; 6-9,000 feet elevation ; July, August. (681.) 
Var. iNERMis, Gray. (7'. inermis, Nutt.) Leaves shorter, acute, but 
scarcely mucronate ; heads smaller ; involucral scales 2-4" long. — Southern 
Oregon to Wyoming, Colorado and New Mexico ; Western Nevada, (Ander- 
son, Bloomer.) Toyabe Range, Huntington and Ruby Valleys, Nevada, and 
Silver Creek Cauon, near Parley's Park, Utah, on dry hillsides ; 6-7,000 feet 
elevation. (682.) 
Tetradymia glabrata, T. & Gr. Pac. R. R. Rep. 2. 122, t. 5. Branches 
white-tomentose ; leaves soon glabrate, somewhat fleshy ; primary ones erect, 
the connective with an ovate acute point, and tlie cells slightly producerl at the base. Style included, 
the branches short, stigmatic to the snnmiit, and crowned with a very short triiucate villous appendage. 
Achenia oblong or top-shaped, densely villous. Pappus of numerous unequal slightly scabrous rather 
rigid bristles, the longest half the length of the corolla. — Low heavy-scented annuals or biennials, viscid 
or mealy-pubescent, with alternate petioled leaves and yellow flowers. Natives of New Mexico, Califor- 
nia, ifcc. 
' TETRADYMIA, DC. Heads 4-floAvered, (in one species 5-9-flowered ; ) the flowers all tubular, 
perfect and fertile; the corollas funnelform with a long slender tube, deeply rj-lobed, tlic linear lobes 
slightly recurved. Involucre of 4 (rarely 5-6) subequal concave-carinate rigid oblong scales. Receptacle 
very small, naked. Anthers linear, exserted. Branches of the style linear, with very short ovate obtuse 
pubescent appendages. Achenia oblong-linear, villous or glabrate. Pappus copious, of very fine unequal 
capillary denticulate filaments as long as the tube of the corolla. — Low much-branched shrubs, of Oregon, 
California, New Mexico, &c. ; often densely white-tomentose, with small rigid linear or subulate sessile 
alternate leaves, the primary ones often becoming spiny. Heads rather large, solitary on short branch- 
lets, or forming small terminal and subterminal clusters; flowers yellow. 
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