26 KEY TO THE SPECIES 



and shining ; achenes with a short beak. Moist hillsides and draws. Very early 

 spring. 



2. Ranunculus inamoenus Greene (Homely Buttercup). Taller, at length 

 20 cm. or more high, sparsely pubescent ; root-leaves broadly oval, crenately 

 toothed at summit, on petioles 2-3 times as long as the blade ; stem-leaves sessile, 

 ternately divided into oblanceolate segments ; petals 5, obovate-oblong, about 5 

 mm. long ; achenes pubescent, in a small ovoid head. Moist parks and valleys. 



* * Leaves all cleft or parted ; tall (20-30 or more cm. high). 



3. Ranunculus acriformis Gray (Wyoming Buttercup). Tall and slender, 

 often 3 or more dm. high, pubescent ; leaves all 3-5-parted, the segments 2-3-clef t 

 into linear divisions ; petals broadly obovate, 5-7 mm. long ; achenes with a broad 

 curved-hook beak shorter than the body. Common in wet meadows and on 

 grassy stream banks. 



4. Ranunculus Macounii Britt. (Macoun'^s Buttercup), Stems coarse, 

 2-6 dm. high, with spreading branches, the whole plant rather roughly hairy; 

 leaves large, 3-divided to the base, the ovate divisions (leaflets) variously parted 

 and cleft into acute segments]; petals about 5 mm. long ; achenes in a sub-globose 

 head, with a short pointed beak. 



5. Ranunculus eremogenes Greene. A light-green, very glabrous plant, 

 with thick or swollen hollow stems, 1-2 dm. high ; leaves 5-parted and the seg- 

 ments lobed, the lobes toothed ; petals light yellow, longer than the sepals ; the 

 numerous achenes in an oblong head, small, smooth, and nearly beakless, falling 

 from the receptacle when dry. Very common in the margins of spring bogs and 

 ponds. 



10. BATRACHIUM (Water- crowfoot) 



Perennial aquatic herbs, with finely dissected leaves and white flowers ; other- 

 wise nearly as in Ranunculus. 



1. Batrachium trichopliyllum (Chaix) Bossch. (White Water-crow- 

 poot). Submerged ; stems slender ; leaves petioled, the segments linear ; flowers 

 on stout peduncles, blooming at the surface of the water ; achenes beakless. In 

 ponds and sluggish streams, 



11. CYRTORHYNCHA 



Characters nearly those of Ranunculus ; the long-petioled blpinnately divided 

 or compound leaves, the narrowly spatulate petals, and the longitudinally ribbed, 

 thin-walled, slightly inflated achenes will serve to distinguish it. 



1. Cyrtorhyncha ranunculina Nutt. (Nuttall's Buttercup). Tufted, 

 with many slender stems and long-petioled root-leaves, 1-2 dm. high ; leaflets with 

 oblong or linear lobes; sepals yellowish, almost as long as the petals ; achenes in a 

 globular head, oblong-cylindric, tipped with the incurved style. 



12. OXYGRAPHIS 



Much like Ranunculus, but the stems scape-like, the achenes flattened and 

 longitudinally striate on the faces, 



1, Oxygraphis Cymbalaria (Pursh) Prantl. (Seaside Crowfoot). Small, 

 mostly less than 1 dm. high, spreading by runners which root at the nodes ; leaves 

 mostly basal, oval with cordate base : flowers 1-5 ; the petals 5-9 ; achenes in an 

 oblong head, tipped with a sharp point. Common on wet alkaline flats and ditch 

 banks. 



