124 RANUNCULACEAE. 



11. R. septentrionalis Poir. Stems 3-12 dm. long, glabrous or pubescent: 

 leaf -blades thickish, the divisions iucised-toothed and often lobed: petals 

 bright-yellow, 10-14 mm. long: head of fruit globose to oval: achene-body 4-5 

 mm. long, wide-margined, the slender beak shorter than the body. — Common, 

 in low grounds and swamps. — Spr. — Swamp-buttercup. 



12. B. fascicularis Muhl. Stems 1-3 dm. tall, densely silky: leaf -blades thick, 

 those of the lower leaves with typically cuneate-flabellate lobed or parted 

 divisions: petals 8-14 mm. long: head of fruit globose: achene-body 2.5-3 

 mm. long, slightly margined, the beak as long, slender. — Common, in woods 

 and thickets. — Spr. — Early-crowfoot. 



13. R. hispidus Michx. Stems 2-6 dm. tall, hirsute or villose-hirsute : leaf- 

 blades pubescent, those of the lower leaves generally 3-parted, the divisions 

 suborbicular to cuneate, incised, lobed, or sometimes parted: petals 9-16 mm. 

 long: head of fruit globose to oval: achene-body 2.5-3 mm. long, slightly 

 margined, the beak about i as long as the body. — Common, in woods and 

 thickets. — Spr. 



12. THAIjICTRUM [Tourn.] L. Perennial herbs. Leaf -blades ter- 

 nately decompound. Flowers perfect, polygamous, or dioecious, often numer- 

 ous. Sepals 4-5. Petals wanting. Stamens numerous, conspicuous. Carpels 

 commonly few. Achenes ribbed or nerved, sometimes stipitate. — Meadow-rue. 



Stamens drooping : filaments filiform ; anthers linear : achenes ribbed, sessile. 



1. T. dioicum. 

 Stamens spreading : filaments spatulate ; anthers oblong : achenes 



ridged, short-stipitate. 2. T. polygamum. 



1. T. dioicum L. Plants 3-6 dm. tall: cauline-leaves with long petioles; blades 

 of the leaflets thin, the terminal ones 1.5-3 cm. wide, lobed: carpels sessile: 

 achene-bodies 3-4 mm. long, abruptly beaked, blunt-ribbed. — Common, on 

 rocky hillsides. — Spr. — Early meadow-rue. 



2. T. polygamum Muhl. Plants 9-30 dm. tall: cauline leaves sessile; blades 

 of the leaflets thinnish, prominently lobed, green beneath, the terminal one 

 mainly 1.5-4 cm. wide: achene-body 4-5.5 mm. long, gradually beaked, sharp- 

 ridged. — Common, in swamps and low meadows. — Sum. — Tall meadow-rue. 



13. CLEMATIS L. Perennial vines. Leaf -blades 3-several-foliolate. 

 Flowers dioecious or polygamo-dioecious, in broad paniculate cymes. Sepals 

 relatively small, but petaloid, without a border, thin, spreading, white or pale. 

 Petals wanting. Stamens spreading: anthers short, blunt. Carpels several. 

 Achenes with silky or plumose styles. 



1. C. virginiana L. Plants sparingly pubescent or glabrate: leaves mainly 

 3-foliolate: sepals whitish, thin, 8-12 mm. long: achene-bodies 4-5 mm. long, 

 very inequilateral. — Common, in thickets and along streams. — Sum. — 

 Virgin 's-bower. 



14. ATRAGENE L. Perennial vines. Leaf-blades several-foliolate. 

 Flowers solitary on axillary branches. Sepals mostly 4, thin, petal-like, large, 

 veiny. Petals small, spatulate. Stamens numerous, erect, the outer more or 

 less petal-like; anthers oval. Carpels several. Achenes with long plumose 



styles. 



1. A. americana Sims. Stems purple, trailing or diffuse: leaflets ovate to 

 ovate-lanceolate, 2.5-9 cm. long, mostly toothed or somewhat lobed: sepals 

 purplish-blue, 3-5 cm. long: petals 8-13 mm. long: achene-bodies 3-4 mm. 

 wide, with style-tips 3-4 cm. long. — Eare, on rocky hillsides and in rocky 

 woods. — Spr. — Bell-rue. 



