Petrak, Die nordamerikanischen Arten der Gattung Cirsium. 515 
angustata semiamplexicauli sessilia, breviter decurren- 
tia, alis angustissimis s p i n u 1 o s o - c i 1 i a t i s , 
ambitu lanceolata, alte et dense sinuato- 
pinnatifida, laciniis inaequaliter bi- vel 
tridentatis, dentibus anguste triangulari- 
bus vel triangulari-lanceolatis, abruptius- 
cule acuminatis spinis subvalidis vel validis 
stramineis 5 — 8 mm longis terminatis; caulina 
superiora gradatim sed parum minora inferioribus simillima; 
caulina suprema e basi late ovata profunde spinoso-dentata ambitu 
lanceolata, non vel brevissime decurrentia, sub- 
remote sinuato-dentata, dentibus late triangularibus vel ovato- 
triangularibus subobtusis vel abruptiuscule acuminatis, ceterum 
ut folia caulina inferiora. 
Capitula in apice caulis et ramorum 2 — 6 subaggre- 
gata, saepe fere spicatim disposita, sessilia 
vel breviter pedunculata, bracteis 1 — 3 
multo brevioribus lineari-lanceolatis, re- 
mote s p i n o s o - d e n t a t i s suffulta, ovato-ob- 
longa vel cylindracea, basi non vel perparum dilatata, 
abrupte in pedunculum attenuata, cum flosculis 3 x / 2 — 4 cm longa, 
12 — 15 mm lata. Involucri glabrescentis vel parcis- 
sime arachnoidei foliola exteriora e basi ovato- 
oblonga lanceolata, abruptiuscule acumi- 
n a t a , dorso interdum subcarinata, spinis subvalidis 
stramineis plus minusve e r e c t o - p a t e n t i b u s 
6 — 10 mm longis terminata, interiora gradatim 
longiora lanceolata, intima multo longiora lineari-lanceo- 
lata, elongato-acuminata, appressa, nec rigida. 
Corollae purpureae vel roseae limbus plus quam ad 
duas tertias fere aequaliter quinquefi dus, 
laciniis angustissimis linearibus, abrup- 
tiuscule acuminatis, a tubo non vel vix 
distinctus eoque plus duplo longior. 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 x / 2 — 3 mm lata, nitida. 
Perenne ? Floret Junio — August o. 
Synonyma: 
Cnicus Rothrockii var. diffusus Eastwood in Proc. Calif. 
Acad. Sei. 2. Ser. VI., p. 303 sec. Eastwood 1. c. 3. Ser. I, 3, p. 121 
(1897—1900). 
Cnicus diffusus Eastwood in Proc. Calif. Acad. Sei. 3. Ser. I, 
3, p. 121 (1897—1900). 
Carduus diffusus Heller in Muhlenbergia I, p. 6 (1900). 
Cirsium diffusum Petrak in schedis 1914. 
Distrib u t i o: In declivibus apricis, lapidosis vel saxosis, 
secus rivulos, in pratis aridis montanis in regionibus meridionali- 
orientalibus Utahensibus dispersum. 
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