AKISTOl.OCHIACE^. (lilRTHWORT FAMILY.) 445 



§ 1 Calyx-tube whoUtj adnate to the ovary, the tips injlexed in hud ; Jilaments 

 slender, much longer than the short anthers ; style barely 6-lobed at the sum- 

 mit, with 6 radiating thick stigmas ; leaves a single pair, unspotted. 



1. A. Canadense, L. Soft-pubescent; leaves membranaceous, kidney- 

 shaped, more or less pointed (4-5' wide when full grown) ; calyx bell-sliaped, 

 tlie upper part of the short-pointed lobes widely and abruptly sjn-eading, 

 brown-purple iuside. — Hillsides iu rich woods ; common, especially northward. 

 § 2. Calyx-tube injiated bell-shaped, somewhat contracted at the throat, its base 



adnate to the lower half of the ovary ; limb 3-cleft, short ; anthers sessile or 

 nearly so, oblong-linear ; styles ^, fleshy, diverging, 2-cleft, bearing a thick 

 extrorse stigma below the cleft; leaves thickish, persistent, usually only one 

 each year, often whitish-mottled ; peduncle very short ; rootstocks clustered, 

 ascending. 



2. A. Virglnicum, L. Nearly glabrous; leaves round-heart-shaped 

 (about 2' wide) ; calyx short, reticulated within ; antliers pointless. — Va. to 

 Ga., in and near the mountains. 



3. A. arifolium, Michx. Leai-es halberd-heart-shaped {2 -4' long); calyx 

 oblong-tubular, with very short and blunt lobes; anthers obtusely short-pointed. 

 — Va. to Fla. 



2. ARISTOLOCHIA, Tourn. Birthwoi.t. 

 Calyx tubular ; the tube variously inflated above the ovary, mostly contracted 

 at the throat. Stamens 6, the sessile anthers wholly adnate to the short am! 

 fleshy 3 -6-lobed or angled style. Capsule naked, septicidally 6-valved. Seeds 

 very flat. — Twining, climbing, or sometimes upright perennial herbs or shrul)s, 

 with alternate leaves and lateral or axillary greenisli or lurid-purple flowers 

 (Named from reputed medicinal properties.) 



§ 1. Calyx-tube bent like the letter S, enlarged at the tivo ends, the small limb ob- 

 tusely S-lobed ; anthers contiguous in pairs {making 4 cells in a row under 

 each of the three truncate lobes of the stigma) ; low herbs. 



1. A. Serpentina, L. (Virginia Snakeroot.) Stems (8 -15' high) 



branched at base, pubescent ; leaves ovate or oblong (or narrower) from a heart- 



jshaped base or halberd-form, mostly acute or pointed ; flowers all next the 



root, short-peduncled. — Rich woods. Conn, to Fla., west to Mich., Mo., and 



La. July. — The fibrous, aromatic-stimulant root is well known in medicine. 



§ 2. Calyx-tube strongly curved like a Dutch pipe, contracted at the month, the 



short limb obscurely 3-lobed ; anthers contiguous in pairs under each of the S 



sho7-t and thick lobes of the stigma; very tall twining sk7'ubs ; flowers from 



one or two of the superposed accessory axillary buds. 



2 A. Sipho, L'Her. (Pipe-Vine. Dutchman's Pipe.) Nearly gla- 

 brous ; leaves round-kidney-shaped (sometimes 8- 12' broad) ; peduncles with a 

 clasping bract ; calyx (1 ^' long) with a brown-purple abrupt flat border. — Rich 

 woods, Penn. to Ga., west to Minn, and Kan. May. 



3. A. tomentosa, Sims. Downy or soft-hairy ; leaves round-heaH-shaped , 

 very veiny (3-5' long) ; calyx yelloivish, with an oblique t?ark purple closed ori- 

 fice and a rugose reflexed limb. — Rich woods, mountains ^ N. C. to Fla., west 

 to S. 111. an«^ Mo. June. 



