Parr 3, 1908] ROSACEAE 279 
stipules of the basal leaves linear-lanceolate, those of the stem-leaves lanceolate and more 
foliaceous; stem-leaves few, with fewer and narrower leaflets and lobes; inflorescence 3-4- 
flowered, with strongly ascending branches; hypanthium hemispheric, about 4 mm. wide, 
sparingly pilose and glandular-puberulent; bractlets narrowly linear, 2-3 mm. long; sepals 
lanceolate-acuminate, about 4 mm. long; petals obcordate, rather deeply notched, 5 mm. 
long; filaments much dilated, lanceolate, unequal. 
Type collected under pines among rocks, White Mountains, California, at an altitude of 
3300 m., in 1888, W. AY. Shockley 596 (Gray Herbarium). 
VI. Tridentatae. Stems slender and ascending; leaves pinnate with 24 pairs of 
cuneate leaflets, which are 2-3- (seldom 5-) toothed at the apex or entire. Hypanthium 
cupulate or campanulate. Petals oblanceolate or spatulate, unguiculate, white or yellow- 
ish. Stamens 10; filaments often linear-lanceolate. Pistils few, 5-15. 
28. Horkelia tridentata Torr. Pacif. R. R. Rep. 4: 84. 1857. 
Ivesia tridentata A. Gray, Proc. Am. Acad. 7: 338. 1868. 
Horkelia Tilingi Regel, Acta Hort. Petrop. 1: 153. 1871. 
Poltentitla Tilingt Greene, Pittonia 1: 105. 1887. 
Perennial, with a deep taproot and short cespitose caudex; stems several, ascending 
or decumbent, 2-4 dm. high, silky-villous, simple; stipules very variable, sometimes 
ovate and entire, sometimes finely dissected; basal leaves numerous, grayish- or white- 
silky, or glabrous on the upper surface, pinnate, with 3-4 pairs of cuneate or obovate 
leaflets, which are generally 3-toothed at the apex (rarely 4-5-toothed), and about 1 cm. 
in length; stem-leaves smaller, with 1 or 2 pairs of leaflets; cyme often somewhat 
branched, with sub-capitate small clusters at the end of the branches or the simple 
stem; hypanthium silky-villous, cup-shaped, in fruit 3-4 mm. in diameter; bractlets 
linear, a third to a half the length of the broadly ovate sepals, which are 1-2 mm. long; 
petals oblanceolate, a little longer than the sepals; filaments all linear-lanceolate; pistils 
5-10. 
TYPE LOCALITY: Wet ravines, Duffield’s Ranch, Sierra Nevada, California. 
DISTRIBUTION: Mountain regions of California ‘and southern Oregon. 
ILLUSTRATIONS: Pacif. R. R. Rep. 4: /. 6; Gartenflora 1872: pl. 711, f. 1-3 ; Mem. Dep. Bot. 
Columbia Univ. 2: p/. 74. 
29. Horkelia integrifolia (Wood) Rydberg, sp. nov. 
Horkelia tridentata integrifolia Wood, in herb. 
Perennial, with a taproot and short cespitose caudex; stems several, ascending, or 
decumbent at the base, 3-4 dm. high, sparingly pubescent with appressed hairs; sti- 
pules lanceolate, entire; basal ‘leaves numerous, 3-6 cm. long, silky-canescent on both 
sides with appressed pubescence; leaflets 2-3 pairs, elliptic, entire or minutely toothed at 
the apex, about 1 cm. long; stem-leaves small, with oblong or lanceolate leaflets ; inflor- 
escence as in HY. tridentata; hypanthium sparingly silky-villous, cup-shaped, in fruit 3 
mm. wide; bractlets linear, shorter than the lanceolate sepals, which in fruit are about 2 
mm. long; petals white, oblanceolate, a little exceeding the sepals; filaments linear- 
lanceolate. 
Type collected on ‘‘Mt. Hook’ [Mt. Hood 7], in 1866, A. Wood 815 (herb. Columbia Univ.). 
30. Horkelia flavescens Rydb. Mem. Dep. Bot. Columbia 
Univ. 2: 138. 1898. 
Tufted plant, with a perennial deep root ; stems several, subscapose or with a few small 
leaves, sparingly silky-villous, scarcely more than 1 dm. high; basal leaves numerous, 
sparingly silky-villous, pinnate, with 3 or 4 pairs of cuneate or obovate leaflets, which are 
about 1 cm. long and 2-3-toothed at the apex; cyme much contracted, dense, subcapitate ; 
hypanthium silky-villous, cupulate, more or less tinged with brown; bractlets linear, about 
half as long as the ovate-triangular sepals, which are about 3 mm. long; petals spatulate or 
obovate, unguiculate, yellowish, at least in thedry state, a little exceeding the sepals; fila- 
