Part 4, 1908] ROSACEAE 
Leaflets oblanceolate or obovate, toothed or cleft except at the very 
base ; stem usually 1-2-dm. high, more or less leafy, several- 
flowered. 
Leaflets deeply cleft ; the clefts extending at least halfway to 
the midrib. 
Inflorescence dense and congested. 
Leaflets 2.5-3.5 cm. long, glabrous above and strongly 
veiny ; sepals 7-8 mm. long. 
Leaflets 1-2 em. long, silky above and indistinctly veiny ; 
sepals about 4 mm. long. 1 
Inflorescence open, with slender pedicels. 
Leaves loosely white-silky on both sides; caudex with 
elongate branches densely covered by the remains of 
old leaves. 106. 
Leaves green above ; caudices short. 
Sepals lanceolate ; bractlets linear-lanceolate ; leaflets 
broadly obovate ; basal leaves, at least some of them, 
5-foliolate. 
Sepals linear-lanceolate; bractlets narrowly linear; 
leaflets narrowly obovate or oblanceolate ; leaves 
104. 
101. 
P. prostrata. 
05. P. Hookeriana, 
P, Pedersentt, 
P. quinquefolia. 
rarely 5-foliolate. 107. P. nipharga. 
Leaflets coarsely toothed ; the toothing rarely extending half- 
way to the midrib. 108. P. nivea. 
Leaflets broadly cuneate, toothed only above the middle; stems 
usually less than 1 dm. high, scapiform, 1-2-flowered (rarely 3- 
flowered). E 109. P. uniflora. 
Bractlets oval or elliptic, sometimes ovate. 
Stem low, scapiform, 1-2-flowered, less than 1 dm. high; leaves 
not strongly ribbed. 110. P. Vahliana, 
Stem 1-3 dm. high, usually several-flowered; leaves with promi- 
nent ribs. 111 
XXIII. FRIGIDAE 
(Leaflets all sessile or short-stalked. 
Stem 1-3 dm. high, erect, leafy. 
Leaflets broadly cuneate-obovate or flabelliform, not glandular ; 
those of the stem-leaves much larger than the stipules; petals 
8-10 mm. long. . 
Leaflets cuneate-flabelliform, glabrate or short-pubescent ; those 
of the stem-leaves often cleft. 
Leaflets broadly cuneate-obovate, decidedly long-pubescent, 
coarsely crenate. 11 
Leaflets obovate or broadly oblanceolate, 3-4-crenate at the apex, 
somewhat glandular; those of the stem-leaves scarcely longer 
than the long stipules; petals about 6 mm. long. 11 
Stem less than 1 dm. high, decumbent; stem-leaves few, reduced. 
Petals much exceeding the sepals. 115. 
Petals scarcely exceeding the sepals. 116. 
Terminal leaflets long-stalked. 122. 
XXIV. BIFLORAE 
One species. 117. 
XXV. SaxOSAE 
Leaflets of the basal leaves 7-9, cleft. 118. 
Leaflets of the basal leaves 3-5, crenate. 
Leaflets thick ; bractlets ovate. 119, 
Leaflets thin ; bractlets linear-lanceolate to oblong. 120. 
XXVI. BREVIFOLIAE 
Leaves pinnate with 5 leaflets. 121. 
Leaves pinnately 3-foliolate. 122. 
XXVII. RUBRICAULES 
Leaves mostly greenish above, tomentose beneath. 
Sepals lanceolate or linear. 
Segments of the leaves linear; stem nearly erect, slender ; sepals 
almost linear. 123. 
Segments of the leaves lanceolate or oblong; sepals lanceolate. 
Segments lanceolate, acute. 
Leaves densely white-tomentose beneath ; pubescerice of the 
petioles spreading. 124. 
Leaflets only slightly tomentose beneath ; pubescence of the 
petioles appressed. 141. 
Segments oblong to orbicular, obtuse. 
Segments of the leaves narrowly oblong. 125 
Segments of the leaves oval to orbicular. 
Sepals broadly ovate-triangular. 
Plant densely cespitose ; segments of the leaves obtuse. 
Plant with spreading branches ; segments of the leaves acute. 
126. 
. P. villosa. 
12. P. flabellifolia. 
4. P. fragiformis. 
3. P. Friesiana, 
emarginala, 
Robbinsiana. 
Grayana, 
SAX OSA. 
rosulata, 
P. 
P, 
P. 
P, biflora. 
P. 
P. 
P. acuminata, 
P. brevifolia, 
P. Grayi, 
P. tenerrima, 
P. rubricaulis, 
P. viridior. 
P. rubripes. 
P, minutifolia, 
127. P. saximontana. 
100. 
PL, divisa, 
299 
