RYDBERG: Rocky MouNTAIN FLORA 469 
auriculate-clasping; heads in a rather dense corymb, 8-9 mm. 
high; involucres somewhat turbinate and floccose at the base, 
5-6 mm. high, 6-7 mm. broad; bracts linear, acute, carinate, 
brownish-black on the backs, yellowish brown on the margins; 
rays orange, about 6 mm. long, 2 mm. wide; achenes glabrous. 
This species resembles most the eastern Senecio tomentosus 
in habit and pubescence, but differs in the shorter blades of the 
basal leaves, which are obovate or oval instead of ovate, in the ¥. 
dark involucres, and the glabrous achenes. It grows in meadows @ 
at an altitude of 1500-2000 m. 
Urau: Near divide, head of American Fork Cafion, July 29, 
1885, Leonard 143 (type, in herb. N. Y. Bot. Gard.); Wahsatch . 
County, near Midway, July 6, 1905, Carlton &G Garrett 970%. US be Hop 
“Senecio Tweedyi sp. nov. 
Senecio flavovirens Rydb. Bull. Torrey Club 27: 181, in part. 3 
1900. A 
Senecio Balsamitae A. Nels., Coult. & Nels. New Man. Cent. 4 
Rocky Mts. 583, in part. 1909. 
Perennial, with a rootstock; stem glabrous, or slightly floccose 
at the leaf-axils, 4-6 dm. high, striate; basal leaves 3-15 cm. long, 
petioled; blades elliptic or oval to oblanceolate, crenate-dentate, 
often lyrate-pinnatifid with a few lobes below the large terminal 
one; lower stem-leaves similar, but more pinnatifid; upper stem- 
leaves deeply pinnatifid, with oblong toothed divisions; heads 
corymbose, 9-10 mm. high; involucres glabrous, somewhat tur- 
binate at the base, about 8 mm. high and as broad; rays narrow, 
bright yellow, 8-10 mm. long and a little over I mm. wide; achenes 
hispidulous on the margins. 
_ This species has been mistaken for Senecio flavulus Greene 
(S. flavovirens Rydb.). In fact, the type was included in the orig- 
inal publication of S. flavovirens and the characters of the achenes 
were drawn from it. The type of S. flavovirens is just in bloom 
and the achenes only slightly developed, but a closer investigation 
shows that they are perfectly glabrous. So are the young achenes 
of all the specimens cited under S. flavovirens except Tweedy 586. 
As this had well-developed achenes, I unfortunately described 
the achenes from it. The type of S. flavovirens and the other 
specimens cited under it, with the single exception mentioned, 
belong to S. flavulus Greene, described a few months earlier. Be- 
