358 SAXIFRAGACEAE 



Leaves mostly narrowed to distinct petioles; plants not strikingly robust, 

 usually 1-4 dm. high. 



Basal leaves almost subcoriaceous, usually shortly and densely viscid- 

 hirsutulous on the upper surface, the blades oblong-elliptic to ovate- 

 elliptic, more or less abruptly contracted into petioles mostly shorter 

 than the blades. 21. S. integrifolia. 



Basal leaves usually fleshy, glabrous or rarely sparsely pubescent on both 

 surfaces, the petioles mostly as long as to longer than the oblong-ovate 

 to deltoid-ovate blades. 22. S. fragosa. 



Cymules open and often raceme-like at maturity. 



Leaf-blades of a distinctly cuneate type, coarsely crenate or serrate-dentate; 



plants 6-15 cm. tall. 23. .S. Howellii. 



Leaf-blades not of a cuneate type. 



Sepals reflexed, at least after anthesis. 



Filaments broadened upward, narrowly petaloid; petals with 2 yel- 

 lowish-green spots toward the base; leaf-blades ovate to oblong- 

 ovate, coarsely dentate, crenate or crenate-dentate. 



24. S. Marshallii. 



Filaments subulate, narrowed rather than broadened above; petals 

 white throughout; leaf-blades oblong-obovate to elliptic, sinuately 

 or repandly toothed. 25. ^. californica. 



Sepals not reflexed, mostly erect even in fruit; leaf-blades coarsely ser- 

 rate or crenate-serrate to crenate. 

 Petals obovate-oblong to narrowly oblong, 2J^ to 4 times as long as 

 the sepals; leaf-blades thin, very sparingly, when at all, pubes- 

 cent. 26. S. fallax. 

 Petals oval to obovate, at most twice as long as the sepals; leaf- 

 blades thick, usually densely rusty-pubescent on the lower surface. 



27. S. occidentalis rufidula. 



1. Saxifraga cernua L. Nodding Saxifrage. Fig. 2236. 



Saxifraga cernua L. Sp. PI. 403. 1753. 



A more or less glandular-pubescent caulescent perennial herb from a small rootstock, usually 

 growing in clumps, the rootstock usually beset with bulblets ; stems leafy, 8-20 cm. tall, un- 

 branched. Leaf-blades reniform, the upper cauline becoming rhomboidal to oblong, the basal 

 and lower cauline crenately to digitately 3-7 lobed, 1-2 cm. wide, on petioles 1-5 cm. long, the 

 upper cauline becoming sessile and bulblet-bearing ; flowers solitary and terminal, the hypanthium 

 very little developed at anthesis, becoming bowl-shaped and 5 mm. wide ; sepals oblong to 

 oblong-lanceolate, 3-4 mm. long, becoming broadly ovate as the hypanthium develops ; petals 

 cuneate-oblong, white, 6-8 mm. long, clawless. Fruit often not developing. 



Rock crevices and meadows, Boreal Zones; circumboreal, extending southward in North America to Labra- 

 dor, Colorado, and but recently collected in northwestern Okanogan County, Washington. Type locality: Lap- 

 land. July-Aug. 



2. Saxifraga Nuttallii Small. Nuttall's Saxifrage. Fig. 2237. 



Saxifraga elegans Nutt. in Torr. & Gray, Fl. N. Amer. 1: 573. 1840. Not Sternb. 1831. 



Saxifraga Nuttallii Small, Bull. Torrey Club 23 : 368. 1896. 



Cascadia Nuttallii A. M. Johnson, Amer. Journ. Bot. 14: 38. 1927. 



Saxifraga Nuttallii var. macrophylla Engler & Irmsch. Pflanzenreich 4 117 : 231. 1916. 



Glabrous caulescent perennial herb from a small rootstock; stems slender, 0.5-3.5 dm. tall, 

 leafy, paniculate above. Leaf-blades oval to cuneate-oblong, the larger shallowly 3-lobed toward 

 the apex, 4-12 mm. long, the lower narrowing to a distinct petiole, the upper inclined to be less 

 and less petiolate; flowers few, in axillary and terminal elongated leafy-bracted racemes or 

 panicles; pedicels filiform, 3-20 mm. long; hypanthium campanulate, including the sepals about 

 3 mm. long, becoming 4.5 or even 6 mm. long in fruit, glabrous; sepals nearly deltoid, 1-1.5 mm. 

 long, acuminate or merely acute ; petals oblong to oblanceolate, clawless, with 3 purple veins, 

 4-5 mm. long; ovary adnate to the hypanthium for about half its length, the carpels united to 

 about the middle, in fruit 4-5 mm. long. 



On wet banks and cliffs, Humid Transition Zone; apparently local, restricted to the hill country about the 

 Willamette Valley, Oregon, and reappearing about Gray's Harbor, Washington. Type locality: banks of the 

 Columbia, near the mouth of the Willamette River. May. 



3. Saxifraga debilis Engelm. Pigmy Saxifrage. Fig. 2238. 



Saxifraga debilis Engelm. in A. Gray, Proc. Acad. Phila. 1863: 62. 1863. 

 Saxifraga cernua var. debilis Engler, Monogr. Saxifr. 107. 1872. 

 Saxifraga rivularis Jepson, Fl. Calif. 2: 121. 1936. Not L. 



Delicate loosely tufted glabrous to glandular-pubescent herb from a small perennial root- 

 stock ; stems 3-10 cm. tall, erect or ascending, very slender, leafy, usually several from the same 

 rootstock, sparingly branched above, the branches ascending, 1-3 cm. long, bearing a solitary 

 flower. Basal leaf-blades thin, reniform to orbicular-reniform. 6-14 mm. wide, crenately and 

 mostly 5-lobed, truncate to slightly cordate at the base, the slender petioles 1-2.5 cm. long, their 

 scarious dilated bases thickly imbricated on the lower portion of the stem ; upper leaves increas- 

 ingly smaller, becoming rhombic-ovate and entire, shortly petiolate ; hypanthium turbinate- 

 campanulate, 3-4 mm. long at maturity; sepals oblong-ovate, 1.5-2 mm. long, obtuse; petals 

 white, spatulate-oblong, 3-6 mm. long, the abrupt claw broadish and very short ; ovary at ma- 

 turity one-half to two-thirds inferior, 6-7 mm. long, the carpels united except for the strongly 

 divergent styles. 



Moist locations, Boreal Zones; of very local distribution within our limits, distributed from British Columbia 

 southward to the Mount Rainier region, the Blue and Wallowa Mountains of eastern Washington and Oregon, 

 and recently collected at several points along the crest and eastern slopes of the Sierra Nevada of California. 

 It is more abundant in the Rocky Mountains of Colorado and Utah, and has also been collected on San Francisco 

 Mountain, Arizona. Type locality: Colorado. July-Aug. 



