RypBERG: Rocky MounrTAIN FLORA 543 
beneath; heads few, ending the stem and short branches, sub- 
tended by narrowly linear spinulose-ciliate leaves, hemispheric, 
about 4 cm. high, 4-5 cm. wide; outer bracts lanceolate, brownish, 
glabrous or nearly so, ending in short weak spines 2-3 mm. long, 
the innermost linear-lanceolate, attenuate, ending in slender 
brownish or purplish somewhat twisted and spreading lance- 
linear tips, these neither dilated nor erose; corollas pinkish; pap- 
pus plumose; tips more or less clavate. 
This species resembles Carduus Kelseyi and C. foliosus in the 
leaves, but differs from both in the scattered few heads and purplish 
stem. In both species mentioned, the heads are conglomerate at 
the end of the stem. In Carduus Kelseyi the involucral bracts 
are much narrower and decidedly arachnoid. In C. foliosus the 
bracts are somewhat broader than in C. Butleri, the inner ones 
have dilated, lanceolate and erose tips, and the leaves are usually 
more lobed. 
Montana: Big Fork, July 28, 1908, B. T. Butler, 674 (type, 
in herb. N. Y. Bot. Gard.); also near Rost Lake, 677. 
‘ Carduus lacerus sp. nov. 
Probably biennial; stem stout, 6-10 dm. high, sparingly arach- 
noid, angled and striate; lower leaves oblanceolate, 2-3 dm. long, 
pinnatifid, with rather broad, ovate or lanceolate divisions ending 
heads more or less clustered, about 4 cm. high and broad; outer 
bracts ovate-lanceolate, glabrous, without glutinous ridge, ending 
in short stout spreading spines 3-5 mm. long; inner bracts with 
dilated, ovate, abruptly acuminate, erose and crisp, spreading 
tips; corollas rose-colored; pappus plumose; tips slightly clavate. 
This species was probably included in Cnicus scariosus by 
Gray, judging from his description in the Synoptical Flora; but 
it is not Cirsium scariosum Nutt., for Nuttall characterized the 
latter as having arachnoid-hairy involucres, the bracts with dilated 
erose tips, and the leaves tomentose beneath. I know of only 
one species which agrees with this characterization. This is well 
represented by Flodman 880, which was distributed as Carduus 
Hookerianus. 
Uran: Wahsatch County, near Midway, July 6, 1905, Carlton 
