338 COMPOSITZ XANTHIUM 
RUDBECKIA 
ularly serrate: fruiting involucre about an inch long, densely beset with 
rather long prickles, the stout beaks at maturity usually hooked at the tip 
or incurved, the surface and base of the prickles more or less hispid, some- 
times glabrate. Sandy shores and waste places Brit. Columbia to Califor- 
nia and the eastern States, 
* * Leaves attenuate at both ends, short-petioled ; their axils triply 
spinescent, 
X..spinosum L. sp. 987. Stems stout. 1-2 feet high, much branched: 
leaves ovate-lanceolate with cuneate base, the larger 3-lobed or incisely 
pinnatifid, green and glabrate above, white-tomentose beneath, with long 
and slender 3-parted yellow spines in the axils: fruiting involucre solitary 
or few, in upper axils, cylindraceous, half-inch long, obtuse, armed with 
short weak prickles, inconspicuously 1-2 beaked or pointless 
Subtribe wii, Verbesiner Less. Rays ligulate and either fertile 
or neutral, not rarely wanting, the ligule not becoming papery and 
persistent on the fruit, but sometimes marcescent. Disk-flowers her- 
maphrodite and fertile or often some of the inner ones sterile, sub- 
tended and sometimes enwraped by the chaff of the receptacle. An- 
thers often blackish. Achenes various but those of the disk never 
obcompressed. Pappus cupulate or coroniform, orof teeth or awns 
from the principal angles, or of some squamelle, or of a few stout 
bristles, or none. 
39 RUDBECKIA L. Gen. n. 980. 
Mostly perennial herbs with alternate leaves and rather large 
and showy heads terminating the stem or branches. Hants 
many-flowerd; the ray-flowers neutral, in a single series, those 
of the disk tubular and perfect. Bracts of the involucre folia- 
ceous, in about two series, spreading. Receptacle conical or 
often more or less elongated and spiciform. Disk-corollas with 
a short but usually manifest proper tube and erect or spreadin 
teeth. Style-branches tipped with an acute or obtuse hispid 
appendage. Achenes 4-angled, prismatic, in some species 
quadrangular-compressed. Pappus a coriaceous or firm-scari- 
ous and often 4-toothed crown, sometimes deep and cupuliform. 
sometimes obsolete, or none. 
R. Californica Gray Proc, Am. Acad. vii. 357. Stem simple, 2-6 feet 
high 3-5-leaved, the long and naked peduncle-like summit bearing a single 
large head: leaves finely soft-pubescent, 3-10 inches long, ovate to oblong- 
lanceolate, acuminate, pinnately veined somewhat toothed; the middle 
ones sometimes with a pair of lateral lanceolate lobes at base, uppermost 
sessile, lower tapering into a slender petiole: bracts of the involucre linear: 
rays 2-3 inches long, narrowy! oblong, yellow: disk columnar 1-2 inches 
long, disky brown: achenes compressed-prismatic, 2 lines long, crowned 
with a pappus of 4 irregular thickish chaffy teeth, more or less united at 
base intoacup. Wet meadows and cold spring runs, southwestern Oregon 
to California. 
R. occidentalis Nutt. Trans. Am. Phil. soc. vii, 355. Nearly glabrous 
and smooth, or somewhat scabrous-puberulent: stems stout, 2-8 feet high, 
nearly simple: leaves ovate or ovate-lanceolate, acuminate, entire or irreg- 
ularly and sparingly dentate, 4-8 inches long, upper ones sessile by a 
rounded or subcordate base, lower ones abruptly contracted into a short - 
