angustata semiamplexicauli sessilia, b r e v i t e r d e c u r r e n

Petrak,
Die nordamerikanischen Arten der Gattung Cirsium.
515
angustata semiamplexicauli sessilia, b r e v i t e r d e c u r r e n tia, alis a n g u s t i s s i m i s s p i n u 1 o s o- c i 1 i a t i s ,
a m b i t u l a n c e o l a t a , a l t e et d e n s e
sinuatopinnatifida,
laciniis inaequaliter
bi- vel
tridentatis, dentibus anguste triangu laribus v e l t r i a n g u l a r i - l a n c e o l a t i s ,
abruptiuscule a c u m i n a t i s s p i n i s s u b v a l i d i s v e l y a l i d i s
s t r a m i n e i s 5 — 8 m m l o n g i s t e r m i n a t i s ; caulina
superiora gradatim sed parum minora inferioribus simillima;
caulina suprema e basi late ovata profunde spinoso-dentata ambitu
lanceolata, n o n v e l b r e v i s s i m e d e c u r r e n t i a , sub­
remote sinuato-dentata, dentibus late triangularibus vel ovatotriangularibus- subobtusis vel abruptiuscule acuminatis, ceterum
ut folia caulina interiora.
Capitula in apice caulis et ramorum 2 — 6 s u b a g g r e ­
g a t a , sa.epe f e r e s p i c a t i m d i s p o s i t a , s e s s i l i a
vel
breviter
pedunculata,
bracteis
1—3
multo b r e v i o r i b u s l i n e a r i - l a n c e o l a t i s ,
re­
mote s p i n o s o - d e n t a t i s suffulta,.
ovato-obl o n g a v e l c y l i n d r a c e a , basi non vel perparum dilatata,
abrupte in pedunculum attenuata, cum flosculis 3 / —4 cm longa,
12—15 mm lata. Involucri g l a b r e s c e n t i s v e l p a r c i s s i m e a r a c h n o i d e i foliola exteriora e b a s i o v a t o oblonga lanceolata, abruptiuscule
acumi­
n a t a , dorso interdum subcarinata, s p i n i s s u b v a l i d i s
stramineis plus minusve erecto-patentibus
6 — 10 m m l o n g i s t e r m i n a t a ,
interiora gradatim
longiora lanceolata, intima multo longiora l i n e a r i - l a n c e o lata, e l o n g a t o - a c u m i n a t a ,
appressa, nec rigida.
Corollae purpureae vel roseae l i m b u s p l u s q u a m a d
duas t e r t i a s fere a e q u a l i t e r
quinquefidus,
laciniis angustissimis
linearibus,
abrup­
tiuscule
acuminatis,
a tubo non vel v i X
d i s t i n c t u s e o q u e p l u s d u p l o l o n g i o r . Filamenta
omnino parce breviterque crispule papilloso-pilosa. Pappus sordide
albus flosculis perparum brevior, setis plumosis, apice saepe tantum
scabridis nec clavellatis. Achaenia matura oblonga compressa,
pallide brunnea vel fusca, 6—7 mm longa, 2 / —3 mm lata, nitida.
Perenne ? Floret J u n i o — A u g u s t o .
Synonyma:
Cnicus Rothrockii var. diffusus Eastwood in Proc. Calif.
Acad. Sci. 2. Ser. VI., p. 303 sec. Eastwood 1. c. 3. Ser. I, 3, p. 121
(1897—1900).
Cnicus diffusus Eastwood in Proc. Calif. Acad. Sci. 3. Ser. I,
3, p. 121 (1897—1900).
Carduus diffusus Heller in Muhlenbergia I, p. 6 (1900).
Cirsium diffusum Petrak in schedis 1914.
D i s t r i b u t i o : In declivibus apricis, lapidosis vel saxosis,
secus rivulos, in pratis aridis montanis in regionibus meridionaliorientalibus Utahensibus dispersum.
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