398 RANUNCULACEAE (CROWFOOT FAMILY) 



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

 achenes 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. June- 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 globose 

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

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



27. R. BULB6sus L. (BULBOUS C. or B.) Hairy; stem 

 730. R. Macounii. (3 dm. high) erect from a bulb-like base ; radical leaves 

 Flower x 5 /7- 3-divided ; the lateral divisions sessile, the terminal stalked 

 Carpel x 4%. 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 

 e. N. E. ; rare westw. May-July. Leaves appearing as if pinnate. Petals 

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

 from Eu.) 



28. R. ACRIS L. (TALL C. or B.) Hairy ; stem erect (6-9dm.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, 

 much 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. STEVENI (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. MURICATUS L. Nearly glabrous ; lower leaves roundish or reniform , 

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

 longer than the calyx; carpels flat, spiny -tuber culate 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.) 



31. R. PARVIFLORTJS 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.) 



2. 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- 

 like receptacle (whence the name, from /u>s, a mouse, and ovpd, a tail), the seed 

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

 and 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. 

 (Macoun) ; and reported from e. Va. (Eu.) 



