198 ‘ Saxifragaceae 
BB. Most of the leaves not entire; petals white. 
FE. Plants with perennial very leafy shoots. 
F. Leaves cleft; sepals united only at base; petals 5-7 mm. long; leaf-blade 
7—21 mm. long. W. C. E. 
S. caespitosa L. 
FF, Leaves lobed; sepals united to the middle; petals 1.5—-3.5 mm. long; 
leaf-blade 3—9 mm. long. C. E. (S. oregonensis. ) 
S. adscendens L. 
EE. Plants without perennial leafy branches; flowering stems annual. 
G. Calyx rotate; leaf-blade reniform to rounded, 2—-8 cm. wide. Wei Ge bs 
S. mertensiana Bong. 
GG. Calyx campanulate; leaf-blades reniform to oblong; less than 2 cm. wide. 
H. Sepals acute or acuminate; leaf-blades ovate to oblong, many of them 3- 
lobed. W. S. nuttallij Small 
HH. Sepals obtuse; leaf-blade rounded to reniform, 5—-7-lobed. C. E. 
S. debilis Engelm. 
AA. Leaves all basal. 
I. Filaments subulate to linear. 
J. Petals none; leaves narrowed to petiole-like bases. FE. 
S. apetala Pip. 
JJ. Petals present: 
K. Leaves narrowed to sheathing bases which are not petiole-like. W. C. 
S. oregana, How. 
KK. Leaves with petioles or narrowed to petiole-like bases. 
L. Flowers irregular, the 3 upper petals lanceolate or oblong-lanceolate, the 
2 lower petals elliptic or spatulate-elliptic. W. C. E. (S. nutkana for 
our region.) S. bongardi Presl. 
LL. Flowers regular, the petals about the same in form and length. 
M. Cymules of the inflorescence compact at maturity. 
N. Petals shorter than the sepals. 
O. Petals obovate. E. (S. nidifica for our region. ) 
S. plantaginea Small 
OC. Petals oblong to cuneate. E. 
S. columbiana Pip. 
NN. Petals longer than the sepals. 
P.  Calyx-lobes not reflexed at maturity. W.C. E. 
S. fragosa, Suks. 
PP. Calyx-lobes reflexed at maturity. 
Q. Petals with claws, 2-toothed at apex. W. (Micranthes 
bidens.) §, bideng (Small) 
QQ. Petals without claws, rounded at apex. W. E. (S. sub- 
apetala.) _§, integrifolie, Hook. 
MM. Cymules of the inflorescence open and often raceme-like at matur- 
ity. 
R. Petals about as wide as long, rounded at base, sessile or with a 
very short claw. 
S. Lower leaf-surface green, glabrous or nearly so; petals sessile. 
Meee Er: &. californica Gr. 
SS. Lower leaf-surface red-tomentose; petals with short claw. W., 
C.  (Micranthes rufidula; apparently S. idahoensis. ) 
S. rufidula (Small) 
RR. Petals spatulate, or obovate-cuneate, or cuneate at base. 


