AEISTOLOCHIACE^E. (BIRTH WORT FAMILY.) 359 



DIVISION m. APETALOUS EX6GENOUS PLANTS. 



Corolla none ; the floral envelopes in a single series (calyx), of 

 sometimes wanting altogether. 



ORDER 87. ARISTOLOCHIACEJE. (BIRTHWORT FAM.) 



Climbing shrubs, or low herbs, with perfect flowers, the conspicuous lurid 

 calyx (valvate in the bud) coherent below with the Q-celled ovary, which forms 

 a many-seeded Q-celledpod or berry in fruit. Stamens 6-12, more or less 

 united with the style: anthers adnate, extrorse. Leaves petioled, mostly- 

 heart-shaped and entire. Seeds anatropous, with a large fleshy raphe, and 

 a minute embryo in fleshy albumen. 



1. As ABU HI, Tourn. ASABABACCA. WILD GINGEB. 



Calyx regular; the limb 3-cleft or parted. Stamens 12, with more or less 

 distinct filaments, their tips usually continued beyond the anther into a point. 

 Fruit fleshy, globular, bursting irregularly. Stemless herbs with aromatic- 

 pungent creeping rootstocks bearing 2-3 kidney-shaped or heart-shaped leaves 

 on long petioles, and a short-peduncled flower close to the ground. (An ancient 

 name, of obscure derivation.) 



{ 1. AS ARUM PROPER, Calyx-tube wholly coherent with the ovary : filaments 

 slender, united only with the base of the style, much longer than the short anthers : 

 styles united into one, which is barely 6-lobed at the summit, and with 6 radiating 

 thick stigmas : leaves membranaceous, unspotted, on flowering stems mostly a single 

 pair, with the peduncle between them. 



1. A. Canadeiise, L. Soft-pubescent; leaves kidney-shaped, more or 

 less pointed (4' -5' wide when full grown) ; calyx bell-shaped, with the upper 

 part of the acute lobes widely and abruptly spreading, brown-purple inside ; 

 stamens awn-tipped. Hill-sides in rich woods ; common, especially northward, 

 and along the Alleghanies. April, May. 



i 2. HETEE6TROPA. Calyx-tube somewhat inflated below and contracted at 

 the throat, only its base coherent with the lower part of the ovary ; the limb 3-cleft, 

 short : JUaments very short or none: anthers oblong-linear: styles 6, fleshy, diverging, 

 2-cleft, each bearing a thick extrorse stigma below the deft : leaves thickish, per* 

 gistent, the upper surface often whitish-mottled, alternate on the rootstock : peduncle 

 very short. 



2. A. Airbill if II in, L. Leaves round-heart-shaped (l'-2' wide) ; calyx 

 ventricose-bell-shaped ; anthers pointless. Virginia, and southward, in and near 

 the mountains. May. 



3. A. arifolium, Michx. Leaves halberd-heart-shaped (2' -4' long), 

 calyx oblong-tubular, with very short and blunt lobes ; anthers obtusely short" 

 pointed. Virginia, and southward. May. 



