Petrak, Die nordamerikanischen Arten der Gattung Cirsium. 435 
simillima; caulina suprema multo minora, quasi brac- 
teiformia, lineari-lanceolata, elongato-acuminata, basi tantum 
remote sinuato-dentata, dentibus triangulari-linearibus acuminatis 
spinis brevioribus terininatis. 
Capitula in apice caulis et ramorum solitaria vel 
2 — 3 subaggregata, breviter pedu neu lata, 
ebracteata vel bracteis 1 — 2 minoribus line- 
aribus integerrimis nec margine spinulosis 
vel basi tantum parce spinuloso-dentatis 
suffulta, ovato-globosa, basi parum dilatata sed 
vix excavata, abruptiuscule in pedunculum con- 
tra c t a , cum flosculis 3 x / 2 — 4 x / 2 cm longa, 2 1 / 2 — 3 cm lata. 
Involucri parce arachnoidei foliola exteriora 
^ t media lanceolata paullatim acuminata, 
spinulisinfirmis stramineis 1 — l 1 /^ mm 1 o n g i s 
erecto-patentibus terminatis, dorso non vel 
perparum viscido-carinata, interiora et intima 
gradatim longiora elongato-acuminata, apice interdum 
plus minusve purpurascentia, spinulis valde in- 
firmis stramineis vix rigidis terminata. Corollae a 1 b i d a e vel 
ochroleucae limbus ad medium circiter maequaliter quin- 
quefidus, laciniis angustissimis linearibus subobtusis, a tubo vix 
distinctus eoque parum brevior vel subaequilongus. Filamenta 
dense longiuscule crispule papilloso-pilosa. Pappus sordide albus, 
setis plumosis apice raro tantum scabridis parum clavellatis. 
Achaenia matura mihi ignota. Bienne ? Floret J u n i o — 
A u g u s t o. 
Synonyma: 
Cnicus Pitcheri Torr, in Eaton, Man. 5. ed. p. 180 (1829) 
sec. Gray Syn. Fl. North Amer. II, p. 403 (1886). — Gray in 
Proc. Amer. Acad. X, p. 42 (1874). — Macoun, Catal. Canad. 
PI. I, p. 269 (1883). — Coulter, Man. Bot. Rocky Mount. Reg., 
p. 214 (1885). — Gray, Syn. Fl. N. Amer. II, p. 403 (1886). — 
Watson et Coulter in Grays Man. Bot. N. U. S. 6. ed. p. 295 (1889). 
— Cowles in Bot. Gaz. XXVII, p. 168, 172, 174, 186, 306 (1899). 
Cirsium Pitcheri Torr, et Gray, Fl. North Amer. II, 3, p. 456 
(1843). — Gray, Man. Bot. N. U. S. 5. ed. p. 273 (1868). — Bruhin 
in Verh. Zool. Bot. Ges. XXVI, p. 257 (1877). — Robinson et 
Fernald, Grays New Man. Bot. 7. ed. p. 857 (1908). — Starr in 
Bot. Gaz. LIV, p. 268 (1912). 
Carduus Pitcheri Porter in Mem. Torr. Bot. Club V, p. 345 
(1893 — 94). — Britt. et Brown, Illustr. Fl. North U. S. III, p. 486, 
Fig. 4062 (1898). — Hill in Bot. Gaz. XXIX, p. 427 (1900). — 
Britton, Man. Fl. North Stat. Canad., p. 1032 (1901). 
Distributio: Species endemica in arenosis secus litora 
lacus Superior et Michigan satis frequens. 
Vidi e loco sequenti: 
Illinois: Chicago, Coli. H. H. Babcock. H. Chr. 
28 * 
