Small: North American Plants 277 



Ranunculus cuxeiformis Ranunculus macranthus 



Blades of lower leaves twice- Blades of lower leaves once- 

 divided : corollas 1.5 cm. broad : divided : corollas 3-5 cm. broad : 

 heads of achenes sub<^lobose or heads of achenes oblong to 

 ovoid-globose, receptacle barely cylindric : receptacle elongated : 

 elongated : achenes conspicu- achenes narrowly margined, 

 ously winged, with triangular with subulate slightly curved 

 beaks. beaks. 



Ranunculus Mississippiensis 



Perennial, stolonifcrous, fleshy. Stems stout, about 2 dm. 

 tall, more or less branched : leaves various ; basal or those on the 

 lower part of the stem with ovate or ovate-lanceolate sinuate- 

 dentate blades 1.5-4 cm. long, and elongated petioles, upper leaves 

 with oblong or linear remotely-toothed blades 3-8 cm. long : 

 flowers few : sepals oblong to suborbicular, sparingly pubescent : 

 corollas about 1.5 cm. broad; petals about 9, nearly oblong, deep 

 yellow and lustrous within. 



In low grounds, Arkansas and Mississippi. Spring. 



Arkansas: Varner, Lincoln Co., April 28, 1898; BiisJi, no. 

 12. 



Mississippi: "Alluvions." 1840; Peck. 



Related to Ranunculus oblongifolius, but more robust, with 

 truncate or cordate blades terminating the elongated petioles of the 

 lower or basal leaves and much larger corollas consisting of about 

 nine petals. 



Thalictrum mirabile 



Perennial, slender, glabrous, bright green. Stems erect, 1-3 

 dm. tall, wiry, dichotomously branched above : leaves various, 

 basal usually ternately compound, with petioles about 2 cm. .long ; 

 upper leaves gradually more simple and shorter petioled : leaflets 

 suborbicular or orbicular-reniform, 2-3 cm. broad, very thin, deli- 

 cately nerved, glaucescent beneath, broadly crenate or shallowly 

 crenate-lobed, truncate or subcordate at the base, longer than the 

 petiolules : peduncles hair-like : flowers white : sepals spatulate or 

 rhombic-spatulate, fully 1.5 mm. long : filaments fully 2 mm. long, 

 club-shaped by an abrupt thickening about the middle : fruit 

 spreading at right-angles to the peduncle ; body plump, about 2 

 mm. long, acute, not depressed along the upper side, as long as 

 the filiform stalk or shorter. 



Resembles TJialictruni clavatum but more delicate and smaller 

 throughout, and with very short-petioled basal leaves. The fruit 



