BUTTERCUP FAMILY. 171 



The most common species, everywhere abundant, coloring leagues upon 

 leagues of grassy hills in the late winter and early spring with its profusion 

 of yellow flowers. Running into numerous varieties, which are scarcely dis- 

 tinguishable in any satisfactory way. 



7. R. occidentalis Nutt. var. rattanii Cray. Very similar to H. cali- 

 fornicus, Tjut the leaf-segments commonly broad; petals 5 ; style subulate, 

 forming a curved beak, this longer relatively to the achene which is papillose- 

 roughened and densely hispidulous. 



Openly wooded hills of the higher North Coast Ranges and northward. 



8. R. hebecarpus H. & A. Very slender herb, 5 to 11 in. high, branched 

 above, sparsely villous; leaves thin, rounded or reniform in outline, 3-parted 

 into ovatish entire or notched or lobed divisions, or the upper divided into 3 

 divergent narrowly oblong acute segments; peduncles 3 to (i lines long; flowers 

 minute, yellow; petals of about the same length as the stamens; aehenes few, 

 hispidulous with hooked hairs, orbicular, flat, 1 line long, tipped with a short 

 curved beak. 



Common in foothill country in the shade of oak and other trees: Coasl 

 Ranges; Sierra Nevada. 



9. R. muricatus L. Rather stout and succulent, 3 to 10 in. high; herb- 

 age yellowish green, glabrous; leaves roundish or reniform, deeply 3-cleft, the 

 segments again cleft or toothed; petals 3 to 4 lines long; aehenes 4 lines long, 

 including the stout ensiform beak, the sides very flat, surrounded by a raised 

 border and coarsely muricate or prickly. 



Naturalized from Europe but not common : San Francisco ; Marin Co. ; 

 Cazadero; Humboldt Bay; Knight's Ferry. 



10. R. aquatilis L. Water Buttercup. Perennial; leaves submersed, all 

 many times dissected into filiform or capillary divisions; flowers *4 in. broad 

 or less; sepals deciduous; styles subulate, rarely persisting; aehenes trans- 

 versely rugose, commonly hispidulous, about 11 to 18 in a rather compact 

 round head. 



Ponds and slow streams in the valleys and mountains : Coast Ranges ; 

 Sierra Nevada. Rather common. Sometimes floating leaves are found with 

 oval or orbicular segments. Apr. 



11. R. lobbii Gray. Lobb's Buttercup. Annual; submersed leaves none, 

 or when present, few and as in the preceding; floating leaves 6 lines broad, 

 divergently 3-parted into oblong or ovate lobes, the riiiddle one commonly 

 entire, the lateral notched; stamens 5 to 10; petals withering persistent; 

 style filiform, about 3 times the length of the ovary; aehenes few (4 to 0), 

 rather sharply rugose, the mature ones sometimes with minute black dots. 



Whitening the surface of shallow vernal pools: Marin Co. to Napa Valley. 

 Apr. -May. 



10. THALICTRUM L. Meadow Rue. 



Perennial herbs with tall erect stems from a short rootstock bearing bi- 

 or tri-ternately compound leaves with petiolulate (or some sessile) Leaflets. 

 Flowers many, small, panicled. in ours dioecious. Sepals in pistillate flowers 

 4 to 7, in staminate flowers more commonly 4, greenish or more or less petal- 

 like. Petals none. Stamens numerous with long mucronate anthers on capil- 

 lary filaments. Aehenes 4 to 15, veined or furrowed and usually acute at both 

 ends, sometimes inflated, tipped with the persistent long styles. (Greek thallo, 

 bloom, the application uncertain.) 



