398 BANUNCULACEAB (CROWFOOT FAMILY) 



flowers 1-1.8 cm. in diameter; sepals reflexed in antliesis ; head of fruit ovoid; 

 acheiies small, flat, strongly margined, the faces sometimes a little warty ; style 

 short, erect. — Waste places, ballast, etc., Philadelphia and southw. (Adv. 

 from Eu.) 



25. R. pennsylvAnicus L. f. (Bristly C.) Stout and erect from a usually 

 annual root, hirsute with widely spreading bristly hairs, leafy to the top, 4-6 dm. 

 high ; leaves all ternately divided or compound, the stalked leaflets unequally 

 3-cleft, sharply cut and toothed, acute ; flowers inconspicuous ; sepals reflexed ; 

 carpels obscurely margined, in a short-cylindric head ; receptacle cylindro-conical. 

 — -Wet places. Juue-Aug. (Asia.) 



26. R. Macoiinii Britton. Resembling the last, but the ascending or reclin- 

 ing stems few-leaved, rarely if ever rooting, not always hirsute ; petals (about 



6 mm. long) surpassing the hardly reflexed and soon decidu- 

 ous calyx ; achenes with a stout straight beak, in a gloiose' 

 or ovoid head; receptacle thick, obovoid. {B. hispidus Man. 

 ed. 6.) — Que. to L. Superior, "la.," and westw. Fig. 730. 

 c 27. R. bulb6sus L. (Bulbous C. or B.) Hairy; stem 

 Til). K. Macounii. (3 dm. high) erect from a hulh-like base ; radical leaves 

 Flower X 6/,. 3-divided ; the lateral divisions sessile, the terminal stalked 



Carpel x4%- and 3-parted, all wedge-shaped, cleft and toothed; peduncles 



furrowed ; petals round, wedge-shaped at base ; calyx re- 

 flexed ; carpels tipped with a very short beak. — Fields; very abundant only in 

 f: N. E. ; rare westw. May-July. — Leaves appearing as if pinnate. Petals 

 iften 6 or 7, deep glossy yellow, the corolla more than 2.5 cm. broad. (Nat. 

 I'rom Eu.) 



28. R. XcEis L. (Tall C. or B.) Hairy ; stem erect (6-9 dm.high) ; leaves 

 3-divided ; the divisions all sessile and 3-cleft or parted, their segments cut into 

 lanceolate or linear crowded lobes ; peduncles not furrowed ; petals obovate, 

 nmch longer than the spreading calyx. — Fields; common, especially eastw. 

 June-Aug. — Flowers nearly as large as the last, but not so deep yellow. 

 (Nat. from Eu.) Var. Stbv±ni (Andrz.) Lange. Leaf-segments broadly ob- 

 lanceolate or even obovate-cuneate. — Moist meadows, N. E. and northeastw. ; 

 not rare. (Nat. from Eu.) 



* * Achenes beset with rough points or small prickles ; annuals. 



29. R. MURiciTus L. Nearly glabrous ; lower leaves roundish or reniforni, 

 S-lobed, coarsely crenate ; the upper 3-cleft, wedge-form at the base ; petals 

 longer than the calyx; carpels flat, spiny -tuberculate on the sides, strongly 

 beaked, surrounded with a wide and sharp smooth unarmed margin. — Wet 

 places, e. Va. and southw. (Nat. from Eurasia.) 



30. R. ARVENsis L. Similar to the preceding, but segments of the cauline 

 leaves more narrow and acute ; carpels armed on the thick border as well as the 

 surfaces. — Waste places, N. J. to O. (Sparingly adv. from Eu.) 



c 31. R. pakvifl6eus L. Hairy, slender and diffuse ; lower leaves roundish- 

 cordate, 3-cleft, coarsely toothed or cut ; the upper 3-5-parted ; petals not longer 

 than the calyx; carpels minutely hispid and rough, beaked, narrowly margined. 

 — Waste places, etc., Md. and Va. to Fla. and Tex. (Nat. from Eu.) 



3. MYOStRUS [Dill.] L. Mouse-tail 



Sepals 5, spurred at the base. Petals 5, small and narrow, raised on a slen- 

 der claw, at the summit of which is a nectariferous hollow. Stamens 5-20. 

 Achenes numerous, somewhat 3-sided, crowded on a very long and slender spike- 

 /ike receptacle (whence the name, from fiOs, a mouse, and oipd, a tail), the seed 

 suspended. — Little annuals, with tufted narrowly linear-spatulate root-leaves, 

 jind naked 1-flowered scapes. Flowers small, greenish. 



1. M. minimus L. Fruiting spike 2-5 cm. long ; achenes quadrate, blunt.— 

 Alluvial ground, etc., 111. to Assina., N. Mex., and Fla.; also at Belleville, Ont. 

 i3IacouH) ; and reported from e. Va. CEu.) 



