284 NORTH AMERICAN FLORA [VoLuME 22 
Bractlets oblong or lanceolate. 
Leaves pubescent. 
Petals broadly obovate ; leaflets about 2 mm. long; sepals 
acute. 15. 7. scandularis. 
Petals spatulate ; leaflets about 5 mm. long; sepals acumi- 
nate. 16. LZ. mutabilis. 
Leaves glabrous ; petals oblanceolate. 17. L. lycopodioides. 
Cymes subcapitate. 
Hypanthium campanulate; petals spatulate, shorter than the 
sepals. 18. LZ. Gordoniz. 
Hypanthium cupulate; petals obovate, much exceeding the 
sepals. 19. L. megalopetala. 
Leaflets mostly bHetiespoiated. 
Stamens 5; plant less than 1 dm. high. 
Cymes subcapitate ; hypanthium about 4 mm. in diameter. 20. J. pygmaea. 
Cymes corymbiform ; hypanthium about 3 mm. in diameter. 21. I. Shockleyz. 
Stamens 10; plant 1-1. 5 din. high. 22. L. chaetophora. 
IV. SETOSAE. 
Leaflets obovate or orbicular, with rounded teeth, usually without terminal 
bristles. 23. L. Baileyi. 
Leaflets cuneate, cleft, with oblong, usually bristle-pointed teeth. 24. I. setosa. 
I. Unguiculatae. Stems rather many from the caudex, rather leafy and many-flowered. 
Flowers in more or less contracted corymbiform or subcapitate cymes. Hypanthium tur- 
binate or campanulate. Petals obovate, with evident claws. Stamens 15-20, in J. argyro- 
coma with slightly dilated filaments. Plant more or less silky hairy, not glandular, and 
with numerous leaflets. 
1. Ivesia argyrocoma Rydberg. 
Horkelia argyrocoma Rydb. Mem. Dep. Bot. Columbia Univ. 2: 144. 1898. 
Perennial, with a thick and deep root, crowned by a short caudex covered by brown 
‘hairy scales; stems decumbent or ascending, slender, tinged with brown, silky-villous, the 
lower part, as well as the petioles, covered with long silvery spreading or reflexed hairs 
in a most beautiful manner ; stipules ovate-lanceolate, often toothed, about 5 mm. long; 
basal leaves numerous, 4-7 cm. long, densely white-silvery silky, of very numerous densely 
imbricate leaflets; cymes dense, subcapitate; hypanthium cupulate, silky, in fruit 3 mm. 
in diameter; bractlets oblong, shorter than the ovate sepals, which are about 3 mm. long; 
petals white, spatulate, a third exceeding the sepals; stamens 20; filaments subulate. 
TYPE LOCALITY : California. 
DISTRIBUTION : Mountains of southern California, 
ILLUSTRATION : Mem. Dep. Bot. Columbia Univ. 2: pl. 84. 
2. Ivesia sericoleuca Rydberg. 
fvesia unguiculaia Brewer & Wats. Bot. Calif. 1: 183, mainly, as to description and Lemmon’s 
specimens. 1876. Not J. unguiculata A. Gray, 1868, 
Potentitla unguiculata Greene, Fl, Fran. 1: 68, mainly. 1891. 
Horkelia sericoleuca Rydb. Mem. Dep. Bot. Columbia Univ. 2: 144. 1898, 
Perennial, with a very thick root, crowned with a short caudex covered with brownish, 
densely yellowish-hairy scales; stems several, 3-4 dm. high, erect or ascending, branched, 
silky-villous and rather leafy ; stipules lanceolate, 1-2 dm. long, often pectinately cleft; basal 
leaves numerous, 1-2 dm. long, densely white-silky, pinnate ; leaflets numerous, generally 
over 30, crowded and more or less imbricate; petioles and lower part of the stem silky- 
villous with long and reflexed hairs; leaflets 5~10 mm. long, divided to the base into oblong 
segments; cyme much branched, many-flowered, at first rather dense, in age open, more 
or less flat-topped; hypanthium cup-shaped or campanulate, 3-5 mm. in diameter ; bract- 
lets oblong or lanceolate, about a third shorter than the lanceolate-acuminate sepals, 
which are 4 mm. long; petals white, broadly obovate, clawed, exceeding the sepals, 
truncate or slightly emarginate; stamens 20; filaments filiform. 
TYPE LocaLity : California. 
DISTRIBUTION : Sierra Nevada, California. 
ILLUSTRATION : Mem. Dep. Bot. Columbia Univ. 2: Bl. 85. 
3. Ivesia Pickeringii A. Gray, Proc. Am. Acad. 6: 531. 1865. 
Potentilla Pickeringti Greene, Pittonia 1: 105. 1887. 
Horkelia Pickeringit Rydb. Mem, Dep. Bot. Columbia Univ. 2: 145. 1898. 
