ARISTOLOCHIACEJE. (BIRTHWORT FAMILY.) 445 



1. Calyx-tube wholly adnate to the ovary, the tips inflexed in bud ; filaments 

 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-shaped, 

 the upper part of the short-pointed lobes widely and abruptly spreading, 

 brown-purple inside. Hillsides in rich woods ; common, especially northward. 

 2. Calyx-tube inflated 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 6, fleshy, diverging, 2-cIeft, 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. Virginicum, L. Nearly glabrous ; leaves round-heart-sh<i/>< </ 

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

 Ga., in and near the mountains. 



3. A. arifolium, Michx. Leaves 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. BIRTHWORT. 

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

 at the throat. Stamens 6, the sessile anthers wholly aduate to the short and 

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

 very flat, Twining, climbing, or sometimes upright perennial herbs or shrubs, 

 with alternate leaves and lateral or axillary greenish or lurid-purple flowers. 

 (Named from reputed medicinal properties.) 



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

 tusely 3-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. Serpentaria, L. (VIRGINIA SNAKEROOT.) Stems (8- 15' high) 

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

 shaped 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. Julv. The fibrous, aromatic-stimulant root is well known in medicine. 

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



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

 short and thick lobes of the stigma ; very tall twining shrubs ; 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 (!' 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-heart-shaped, 

 very veiny (3 - 5' long) ; calyx yellowish, with an oblique dark purple closed ori- 

 fice and a rugose reflexed limb. Rich woods, mouutaius of N. C. to Fla., west 

 to S. 111. and Mo. June. 



