40 
540 COMPOSITAE 
bract-like, the basal leaves short-petiolate, the cauline sessile ane decurrent in the spiny wings; 
heads soli tary. modding. | oe mo ostly 3-5 cm. long and 4-8 cm. wide; involucre hemispheric, th 
ate, scarcely spinose, purplish; flowers purple; achenes obovate, 3-4 mm. long, rina 
wr rinkled, bie ish; pappus- -bristles numerous, whitish, 1.5-2.5 cm. long. 
Rar d local weed along roads and in grassy places; Whatcom and wii tman Counties, Washin on 
ballast, ‘Linnton, pyre mah County, beer Walnut, Los Angeles Courity: California; occasional ene ia to 
British — a (Alexis Creek) a nd eastward to the Atl antic; Argentina. Native of the Old World. May-Sept. 
Carduus acant catia ~ as. ‘Pl. on. pobieae Plant biennial, the erect — spinose-w eo leave 
brescent, petrol margined; hea late or hemispheric, solitary or few-clustered, 1.5-2. os, eae and 
octane mar tie 7 phyllaries ae or linear- lanceolate, the outer and middle at “spreading or machiaal. short- 
spino orolla reddish purple, nearly 2 c ong; achene oblong- eevee Pass ng, brown, ob- 
arciy ieneliadinatty nerved and finely transversely rugulose; pappus whitish, cy. : ng. Ne ee Lake 
Waha, Nez Perce County, western Idaho; occasional east to the Atlantic; Argentina. Native a Europ 
2. a tenuiflorus Curtis. Slender-flowered Thistle. Fig. 5937. 
Carduus tenuiflorus Curtis, Fl. Lond. Fasc. 6, pl. 55. 1790-98. 
Carduus neglectus of pen authors, in part. Not Tenore. 
Plants annual, more or less tomentose, the upper side of the leaves glabrescent; stems atstt, 
3-20 dm. tall, aetowly to broadly spiny-winged, simple or fastigiately few-branched from 
the base. Leaves Aaa ey to elliptic or obovate, to 1.5 dm. long an cm. wide, the banat 
shortly petioled and sometimes only gis lly EA Re apantine i and decurrent from the 
n J i pa d in 
e gt al 
and paw ak eure: at the ends of st and branche oP fre sy more than 5 in a cluster ; phyl- 
laries numerous in several series, tay Se lo oosely imbricate, the outer and middle ovate to lanceo- 
r 
sordid-whitish, 1-1. 5 cm 
ssy slopes, open ey and r Coast Ranges from_ notte County, Oregon, to central paeriavi, 
seuainete in the Sierra Nevada foothills — poe Pees toR ; Texas. Native ‘of Europe. April—Aug 
in rm he corolla f 
as the c bia rece sched oblong, 4-5 mm. long, brownish, usually finely 10-13- pie tenet 
. long. 
3. Carduus pycnocéphalus L. Italian Thistle. Fig. 5938. 
Carduus pycnocephalus L. Sp. Pl. ed. 21151. 1763. 
Plants annual, gray-green to white-tomentose, the upper side of the leaves glabrescent, scabrid ; 
stems erect, 1.5-10 (or 20) dm. tall, simple or few- branched, rather narrowly spiny-winged, the 
wing-spines Svaticaie toctnmtal: often ong cae rigid. Leaves oblanceolate or lanceolate to 
oblongish and rarely ovate, to 15 cm. lon —_ cm. wide, pinnately parted into spiny-toothed or 
-lo segments, the terminal spine of the segments and s the most prominent and rigid, the 
basal and lowest cauline leaves short- seticlate. the middle cauline leaves narrowly cuneate, the 
upper So heads cylindric, 2-2.5 cm. long, gene rally 2-5-clustered at the ends of stems 
and branches, or metimes solitary ; chyllties eatin in several series, rather loosely imbri- 
n 
scab rt ic 
midrib, the inner phyllaries Snes, less rigid and nearly innocuous; flowers reddish purple, the 
corolla-lobes about three times as long as the corolla-throat ; achenes oblong, buff or pale brown, 
shining, 6 mm. ppu 2 cm. long. 
On grassy flats and slopes and along ro: oads; widespread and common in the San Francisco Bay area, Cali- 
fornia; local in Lane County, ore n, and in Eldorado and San Diego Counties, California. Native of the 
Mediterranean region. April—June 
144. CRNTOURRA L. Sp. Pl. 909. 1753. 
s 
graduated, the innermost frequently shortened and connivent, or the innermost occasionally 
longest. [An ancient Greek name, signifying the centaurs’ plant, of obscure application] 
A genus of about 400 species, found largely in the Mediterranean r but occ rides also in North a 
South America and Australia. All of ours are introduced. Type species, 'aaeares gone ide m L. 
