202 
stem and virgate branches, heads and flowers as in Pluchea, but invo- 
lucre of fewer and linear or subulate bracts. 
1. P.virgatum DC. Root fusiform and fibrose: stem slender, simple or with 
virgate branches: leaves linear and very acute, entire, or the lower cauline lanceo- 
late and obscurely serrulate: heads narrow, in separated glomerules, forming a vir- 
gate and elongated interrupted spike-like inflorescence: involucre appressed-tomen- 
tose,—Open pine woods near Houston (Lindheimer), and Sutherland Springs, Wilson 
County (Palmer). 
36. EVAX Giertn. 
Low densely floccose-woolly annuals, with many-flowered discoid 
heads, flowers as in Pluchea (the central usually sterile), few woolly in- 
volucral bracts, convex to subulate chaffy receptacle, the scarious chaft 
not embracing the smooth dorsally compressed achenes, anthers with 
tails or acutely sagittate, and no pappus. 
* Chaff of the female flowers naked ; of the staminate flowers woolly-tipped and somewhat 
embracing the fowers : heads aggregated in terminal foliose-involucrate glomerules. 
1. E. prolifera Nutt. Rather stout, simple or branching from the base: leaves 
numerous, small and spatulate: heads cylindraceous or oblong-fusiform, in dense 
proliferous clusters: staminate flowers each on a filiform stipe representing an abor- 
tive ovary.—Dry ground, throughout Texas. 
2. E. multicaulis DC. Rather slender, diffusely branched from the base: leaves 
oblanceolate or spatulate: heads globular or ovoid, the capituliform glomerules much 
smaller and less foliose-involucrate: staminate flowers sessile, without vestige of 
ovary.—Low ground, throughout Texas. In eastern Texas is var, DRUMMONDII 
Gray, a slender form with some long woolly hairs on the limb or on the tube of the 
staminate corollas. 
** Chaff of the female flowers eaternally villous-lanate; of the 5 central flowers very 
woolly and involute around the lower half of the lower: heads axillary. 
3. E. candida Gray. Slender, and withcommonlysimple branches, silvery white 
throughout with appressed wool: heads usually few in a foliose-involucrate cluster 
and sessile or nearly so in the axils of the spatulate or lanceolate leaves.—Alluvial 
or sandy ground, from eastern Texas to the central and northwestern part of the 
State. 
37. ANTENNARIA Gertn. (EVERLASTING.) 
Perennial white-woolly herbs, with entire leaves, corymbed dicecious 
and discoid heads of yellowish flowers, dry and scarious white or col- 
ored imbricated involucre, convex or flat naked receptacle, tailed an- 
thers, terete or flattish achenes, and pappus a single row of bristles (in 
the fertile flowers capillary, united at base so as to fall in a ring, and 
in the sterile thickened and club-shaped or barbellate at summit). 
1. A. plantaginifolia Hook. (PLANTAIN-LEAVED EVERLASTING.) Spreading by off- 
sets and runners, low, 7.5 to 45 cm. high: leaves silky-woolly when young, at length 
green above and hoary beneath; those of the simple and scape-like flowering stems 
small, lanceolate, appressed; the radical obovate or oval-spatulate, petioled, ample, 
3-nerved: heads in a small crowded corymb: involucral bracts of the (mostly white) 
involucre obtuse in the sterile, and acutish and narrower in the fertile plant.—Com- 
mon on sterile knolls and banks. 
