170 BANUNCULACEAE. 



stems Blender or almost filiform, decumbent and creeping, rooting at the 

 joints. \ to 11 in. Ion*;; leaves lanceolate or linear-lanceolate, entire, 1 to 2 in. 

 long, tapering into the petiole; flowers 2 to 5 lines broad; achenes few, thick, 

 less than 1 line long, the beak short. 



Margins of lakes or shallow slow meadow -streamlets: Sierra Nevada at 

 middle altitudes; Humboldt Bay; Pt. Keyes. July. 



2. R. pusillus Poir. var. lindheimeri Gray. Slender annual, 4 to 10 

 in. high, or succulent and only a few in. high; herbage glabrous or the dilated 

 petiole sometimes sparingly villous-ciliate; leaves long-petioled except the 

 uppermost; radical round-ovate, toothed or entire, 3 to 6 lines long; cauline 

 elliptic-oblong to linear-lanceolate, entire or slightly denticulate, 1 to 2 in. 

 long; flowers minute; sepals subscarious, mostly not refloxed ; petals com- 

 monly 1 to 3, less than 1 line long; achenes numerous in a small globose 

 head, papillose, beakless or nearly so. 



Low wet places, rare: Napa Valley; Sonoma; San Rafael. Apr. -May. 



3. R. bloomeri Wats. Glabrous somewhat succulent herb, the stems 5 to 

 1(5 in. high, from a cluster of thick-fibrous or even slender-fusiform roots; a 

 few leaves simple, but mostly trifoliolate, the radical long (1 ft. or less) -petioled ; 

 leaflets roundish, dentate with coarse round teeth, usually petiolulate, sparsely 

 incised or 3-lobed; flowers few and large, 1% in. in diameter or less; petals 

 5, emarginate at apex, the greenish area at base conspicuous and the gland 

 large; achenes turgid, 1% lines long, tipped with a slender subulate beak. 



Low fields near the coast: San Mateo Co.; West Berkeley; Marin Co.; 

 Napa Valley and north to Ukiah and Long Valley (Mendocino Co.).- Feb.- 

 Mar. 



4. R. orthorhyncus Hook. var. platyphyllus Gray. Stems very stout, 

 1*4 to 3i/> ft. long, from a cluster of slender fusiform roots; leaves ternately 

 divided, the divisions broad, sharply or laciniately cleft; radical leaves 3-f olio- 

 late with the leaflets 3-parted or -divided, on long petioles; petals 5 to 8, 

 round-obovate to broadly oblong, 6 to 10 lines long; achenes glabrous, the 

 slender beak as long as the body. — (Var. maximus Jepson.) 



Swampy places: Berkeley; Marin Co.; Humboldt Co. 



5. R. canus Benth. var. hesperoxys Jepson. Herbage fragrant, soft- 

 villous when young or on the under surface of the leaves conspicuously canes- 

 cent; stems l!/o to 2 ft. high; leaves nearly all in a radical tuft, long-petioled. 

 deeply parted and subdivided into many lanceolate acute segments; petals 

 5 to 8; achenes large, flat, 3 lines long, including the short triangular-subulate 

 beak which is slightly curved at the tip. 



Antioch; Montezuma, Piatt, 1902. Mar. R. • canus is very silky-Innate 

 throughout. — Originally collected by Hartweg in the valley fields of Butte Co. 



6. R. calif ornicus Benth. Common Buttercup. Herbage deep green and 

 oearly glabrous, or with a short stiffish pubescence, especially on the leaves, 

 or soft -pubescent throughout ; stems mostly caespitose, erect or decumbent. 9 to 

 L8 in. long, freely branching and many-flowered; leaves roundish in outline, 

 ternately divided,' and again divided, parted or lobed, the earlier with the 

 broad divisions obtusely lobed, the later with the laciniately and sharply 

 cleft divisions less broad or narrowly linear, but in these particulars exceed- 

 ingly variable on the same individual and on different individuals; sepals 

 Usually somewhat petal-like, closely re-flexed ; petals about 9 to 16, obovate to 



oblong, 1 to 5 lines long; achenes flattened :; ( to l'-j lines long, the short and 



rat her stout beak closely recurved. 



