240 NORTH AMERICAN FLORA [VoLUME 34 
pinnatifid, more or less villous; primary divisions oblong in outline, acute, 2-4 cm. long; rachis 
narrowly winged; secondary segments lance-oblong, with lanceolate teeth; heads 1 or 2, 
rarely 3 or 4; involucre depressed-hemispheric, about 6 mm. high, 12-15 mm. broad; bracts 
20-25, in 2 series, hirsute, with brown scarious lacerate margins, the outer lanceolate and 
obtuse, the inner oblong and rounded at the apex; ray-flowers 15-20, in a single series, pistil- 
late; corollas 6-7 mm. long, yellow; ligules broadly obovate, obtusely 3-lobed, 2.5—-4 mm. long, 
about 3 mm. wide; disk-flowers numerous; corollas 4 mm. long; achenes 3 mm. long, somewhat 
angled; pappus a 3—5-lobed erose crown. 
TYPE Loca.ity: Siberia. 
Distripution: Alaska, Yukon, and Mackenzie; also eastern Siberia. 
ILLUSTRATION: Gmel. Fl. Sib. 2: pl. 85, f. 1. 
5. Tanacetum camphoratum Less. Linnaea 6: 521. 1831. 
Omalanthus camphoratus Less. Syn. Comp. 260. 1832. 
Omalotes camphorata DC. Prodr. 6: 84. (1837. 
Tanacetum huronense Nutt. Trans. Am. Phil. Soc. II. 7: 401, in part. 1841. 
Tanacetum elegans Decaisne, Fl. Serres 12: 19. 1857. 
A stout perennial, with a branched rootstock; stem 3-5 dm. high, arachnoid-villous; 
leaves 1-2 dm. long, twice pinnatifid, arachnoid-villous, oval in outline, obtuse; primary divi- 
soins oblong, obtuse, 2—5 cm. long; secondary divisions crowded, oblong, obtuse, cleft into short 
oblong lobes; heads few, 3-12, in a congested corymb, short-peduncled; involucre depressed- 
hemispheric, 5-6 mm. high, 10-16 mm. broad; bracts 25-30, densely arachnoid-villous, the 
outer lanceolate, the inner oblong, obtusish; ray-flowers few, ina single series; corollas tubular, 
flattened, oblique, 3-lobed, 4 mm. long, not longer than the disk-flowers; style shorter than 
the corolla; branches oblong, obtuse; disk-corollas tubular, 5-toothed, 4 mm. long, glabrous; 
style included; branches short, truncate; achenes 4 mm. long, bluntly 3-5-angled, densely 
glandular-granuliferous; pappus a bluntly toothed erose crown. 
Type LocaLity: California. 
DISTRIBUTION: Beaches, California and Oregon. 
ILLUSTRATION: FI. Serres pl. 1191. 
12. SPHAEROMERIA Nutt. Trans. Am. Phil. Soc. II. 7: 402. 
1841. 
Low cespitose perennials, with a woody base, or small shrubs. Leaves alternate, often 
crowded at the base, pinnately or pedately divided or simple, usually (except in one species) 
silvery-canescent. Heads heterogamous but apparently discoid, few, corymbose, or in one 
species in subcapitate clusters and in another solitary. Involucre hemispheric to broadly 
campanulate; bracts few,in 2 subequal series, usually broad. Receptacle conic or convex, 
naked. Marginal flowers (functionally ray-flowers) few, pistillate and fertile, but without 
ligules; corollas cylindric to lance-ovoid, 3- or 4-lobed, slightly if at all oblique; lobes often 
somewhat unequal, if 4 the alternating ones smaller. Disk-flowers many, hermaphrodite 
and fertile; corollas with the usually short tube passing into the campanulate or cylindro- 
campanulate throat. Anthers with ovate obtusish tips. Style of the ray-flowers short- 
exserted, that of the disk included; branches of the former oblong, obtuse, of the latter short, 
truncate and penicillate at the apex. Achenes subcylindric, tapering at the base, 5—10-ribbed. 
Pappus wanting. 
Type species, Sphaeromeria capitata Nutt. 
Low cespitose perennials, with a tufted woody caudex; plant rarely 3 dm. high. 
Heads solitary; leaves or their segments linear. S. simplex. 
Heads several. 
Seer in ee Nee pie leaf- Sauaeaae linear or nearly so. 2. S. capitata. 
corymbose; leaf-segments obovate. . S. argentea. 
Small shrubs, 2-6 dm. high ro ets 
Leaves Ete eae corolla-lobes short-villous. 4. S. cana. 
Leaves glabrous or nearly so; corolla-lobes glabrous. 5. S. diversifolia. 
