235 
** Involucre 1 or 2-flowered, of 1 to 3 unequal bracts : heads densely glomerate. 
4, F. repanda Lag. Divergently branching: leaves obovate to oblong-lanceolate, 
with narrowed petiole-like base, acutely serrate: glomerules of many confluent heads, 
sessile in the forks and involucrate at ends of branches; outermost heads commonly 
of a single short-ligulate flower. (F. Contrayerba Gray, Pl. Wright.)—Southern and 
western Texas. 
95. POROPHYLLUM Vaill. 
Usually glaucous and herbaceous or suffrutescent plants, with alter- 
nate or opposite undivided leaves, pedunculate heads of yellow or pur- 
plish flowers, 5 to 10 equal and distinct involucial bracts dotted or 
striped with oil-glands (as often are the leaves also), small naked recep- 
tacle, no ray-flowers, linear achenes, and simple pappus of copious 
capillary scabrous bristles. 
* Annual, with broad crenate-repand leaves on slender petioles : involucral bracts & : corol- 
las purplish: achenes slender. 
1. P. macrocephalum DC. Leaves roundish-oval to oblong, about as long as the 
petiole: peduncles enlarged above: heads 2.5 cm. long: involucral bracts obtuse: 
achenes much longer than pappus.—Rocky hills and ravines, Limpia Cajon, south west- 
ern Texas (Nealley). A species of Arizona and Mexico. 
** Perennial, with narrow entire sessile leaves: much branched, 3 to 9 dm. high. 
2. P. gracile Benth. Lignescent at base, with slender striate branches: odor pun- 
gent (‘‘ fennel-like”): leaves narrowly linear to filiform: involucre cylindraceous, of 
5 oblong obtuse scarious-margined bracts: corollas dull white and purple: achenes 
attenuate at apex, rather longer than the pappus.—Arid plains of southwestern Texas. 
3. P. scoparium Gray. Shrubby at base, with slender rush-like branches: leaves 
thick and firm, linear-subulate and filiform, mucronate: involucre campanulate, of 
7 to 9 broadly lanceolate greenish bracts: corollas yellow: achenes not attenuate at 
apex, fully equaled by the pappus.—Rocky banks and plains of southwestern Texas. 
96. CHRYSACTINIA Gray. 
A much branched very leafy fruticulose plant, with alternate heath- 
_like leaves, slender-pedunculate heads with golden yellow rays termi- 
nating the branches, involucre of 10 or more short and distinct bracts, 
numerous yellow disk-flowers, small naked receptacle, short-linear 
achenes not attenuate upward, and simple pappus of copious capillary — 
scabrous bristles. 
1. C. Mexicana Gray. Leaves thick or almost terete, short-linear or filiform, 
cuspidate-muconate, entire, with abundant round oil-glands: involucral bracts 
lanceolate and usually bearing a single large and prominent oil-gland just below the 
apex: achenes shorter than pappus.—Rocky ground, western Texas. ‘One of the 
Damianas of the Mexicans; exhaling a strong resinous aromatic odor” (Havard), 
97. NICOLLETIA Gray. 
Low annuals, with alternate irregularly pinnately parted leaves, 
leafy branches terminated by large heads of purple or flesh-colored flow- 
ers, 8 to 12 thinnish distinct involucral bracts, naked receptacle, filiform- 
linear achenes with tapering base, and double pappus (the outer of in- 
