542 COMPOSITAE, Vou. HI, 
g. Senecio frigidus Less. Arctic Senecio. 
Fig. 4018, 
Senecio frigidus Less. Linnaca 6: 230, 1831. 
Perennial, more or less tomentose, or becoming 
glabrous when old; stem slender, 6’-12" high, bearing 
a solitary head (rarely 2 or 3) 4-1 broad. Basal 
and lower leaves spatulate or obovate, 1-2" long, peti- 
oled, obtuse, repand-dentate or entire; stem leaves 
oblong to linear-lanccolate, obtuse or acute, sessile, 
mostly entire, smaller; involucre broadly campanu- 
late, about 7” high, its bracts lanceolate, acute, with 
no exterior smaller ones; rays 10-16, 0-10" long, 
3-toothed, linear-oblong, or cuneate at the base; 
ole glabrous or sparingly pubescent; pappus 
white, 
Labrador and arctic America to Alaska, Also in north- 
eastern Asia. Summer, 
10. Senecio Jacobaéa L. Tansy Ragwort. 
Staggerwort. Fig. 40109. 
Senecio Jacobaea L. Sp. Pl. 870. 1753. 
Perennial by short thick rootstocks, somewhat 
woolly, or glabrous; stems stout, simple, or 
branched above, 2°-4° high, very leafy. Stem 
leaves 2-3-pinnatifid, 2’-8’ long, the lower peti- 
oled, the upper sessile, the lobes oblong-cuneate, 
dentate or incised; basal leaves lyrate-pinna- 
tifid; heads very numerous, 6-8” broad, short- 
peduncled in large compact corymbs; involucre 
narrowly campanulate, about 24” high, its bracts 
linear-lanceolate, acute, green, or tipped with 
black, usually with a few subulate outer ones; 
rays 12-15; achenes of the disk-flowers pubes- 
cent, those of the rays glabrous; pappus white. 
In waste places, Newfoundland and Nova Scotia to 
Maine and Ontario, and in ballast about New York 
and Philadelphia. Adventive from Europe. Stave- 
wort. Cankerweed. Kettle-dock. St. James’-wort. 
Felonweed. Fairies’-horse. Ragweed. Saracen’s-com- 
pass. July—Sept. 
11. Senecio antennariifélius Britton. Cat’s- 
) paw Ragwort. lig. 4620. 
Senecto pi ues te es Britton, in Britt. & Brown, II. 
Fl. 3: 478. 1898. 
Perennial, tufted in mostly large clumps; stems 
slender, 8’-18’ high, loosely white-woolly, Leaves 
nearly all basal, commonly numerous, oval to spatu- 
late, angulately few-toothed or entire, mostly obtuse, 
narrowed into a petiole as long as the blade or longer, 
densely white-tomentose beneath, green and finally 
| labrous above, 1'-24’ long; stem leaves small, spatu- 
ate, laciniate, or the upper narrowly linear and en- 
</ tire; heads several, corymbose, slender-peduncled, 
aes rathed less than 1’ broad; rays golden-yellow, showy ; 
involucre 3” high, white-woolly; achenes glandular- 
pubescent. 
L. 
2 Stony hillsides, mountains of Virginia and West Vir- 
ginia. May-June. 
