ASARACEAE . 1133 



parietal placentae : styles united into a 4-6-angled column. Ovules numerous in each 

 cavity. Capsule pendulous, 4-6-valved. Seeds numerous, horizontal, often ^flattened. 

 Testa hard, crustaceous. 

 Erect herbs. 



Plants sparingly and indistinctly pubescent with soft hairs. 



Leaf-blades hastate, delicate : capsule 5-6 mm. long. 1. A. Nashii. 



Leaf-blades not hastate, membranous : capsule about 1 cm. long. 2. A. Serpentaria. 



Plants manifestly pubescent with stiff spreading hairs. 



Leaf-blades petioled. tirm, not prominently reticulated. 3. A. cnnvolvulacca. 



Leaf-blades nearly sessile, clasping, leathery, prominently reticulated. 4. A. reticulata. 



Twining or prostrate vines. 



Plants herbaceous : limb of the calyx expanded only on one side : stamens 5. 5. A. pentandra. 

 Plants woody : limb of the calyx spreading on all sides: stamens 6. 



Foliage densely tomentose : leaf-t)lades leathery : hypanthium tomentose. 6. A. iomentosa. 

 Foliage minutely pubescent or glabrous : leaf-blades membranous : hypan- 

 thium glabrous. 7. A. macrophylla. 



1. Aristolochia Nashii Kearney. Foliage bright green, finely pubescent. Stems 

 erect or reclining, 1-3 dm. long, flexuous, angled, simple or branched below : leaves deli- 

 cate ; blades very thin, linear or lanceolate, hastate, or the young leaves scmietimes ovate, 

 2-10 cm. long, acuminate, ciliate, short-petioled, cordate at the base : peduncles slender, 

 1-flowered : bracts 2-4 mm. long: Howers brownish purple, 10-12 mm. long: calyx-limb 

 sliglitly o-lobed, about 1 cm. broad : hypanthium pilose : capsules subglobose, 5-6 mm. in 

 diameter, pilose, sharply angled. 



In damp woods, Virginia to Florida and Louisiana. Summer. Sn.\keroot. 



2. Aristolochia Serpentaria L. Foliage deep green, sparingly pubescent. Stems 

 erect, 2-5 dm. tall, simple or branched below, more or less zigzag, angled, leafy above, 

 naked below : leaves few ; blades oblong-lanceolate to oval-lanceolate or rarely lanceolate, 

 4-15 cm. long, acuminate, undulate, cordate at the I)ase, 3-nerved, short-petioled : pedun- 

 cles 1-flowered, bracted, solitary or clustered : bracts 2-3 mm. long : flowers S-shaped, 

 about 1 cm. long : hypanthium inflated at the ovary and at the throat : calyx-limb slightly 

 3-lobed : capsules subglobose, about 1 cm. in diameter. 



In woods, Connecticut to Michigan, Florida and Missouri. Summer to fall. Sn.\keroot. 



3. Aristolochia convolvulacea Small. Foliage bristly-pubescent throughout. 

 Stems erect or decumbent, 1-3 dm. long, angled, slightly zigzag, simple or rarely branched 

 below : leaves few ; blades thinnish, becoming firm at maturity, broadly ovate to oval, 

 2-8 cm. long, short-acuminate or rarely acute, ciliate, deeply cordate at the base ; petioles 

 0.5-1.5 cm. long, hirsute: peduncles slender, 1-2-flowered, zigzag angled: hypanthium 

 densely hirsute : flower 0.5-1 cm. long : calyx-limb 6-8 mm. broad, scarcely lobed : cap- 

 sules subglobose, 6-7 mm. in diameter, pubescent. 



In woods, Georgia. Spring and summer. 



4. Aristolochia reticulata Nutt. Foliage bright green, pubescent. Stems erect or 

 decumbent, 1-3 dm. tall, angled, simple or branched below, zigzag, hirsute : leaves few ; 

 blades oblong, angled, oval or broadly ovate, firm, 3-10 cm. long, obtuse or acutish, un- 

 dulate, prominently reticulated beneath, pubescent on both sides, nearly sessile, clasping : 

 floAvers corolloid, pubescent, dark brown, solitary or in bracted racemes : bracts ovate to 

 to suborbicular. 



On river banks, Arkansas to Louisiana. Summer. 



5. Aristolochia pentdndra Jacq. A diffusely twining vine, with minutely or spar- 

 ingly pubescent foliage. Stems commonly several meters long ; leaf-blades narrowly or 

 broadly ovate, 4-10 cm. long, sometimes slightly 3-lobed, cordate at the base ; petioles 

 shorter than the blades : pedicel slightly shorter than the peduncle : hypanthium minutely 

 pubescent : calyx nearly straight, the small limb not lobed, expanding on one side, nearly 

 erect: capsules globular, 1.5-2 cm. long. 



In thickets, southern peninsular Florida and the Keys. Also in the West Indes. 



6 Aristolochia tomeatosa Sims. A twining vine, with tomentose foliage. Stems 

 often 10 m. long, woody : leaf-blades firm, broadly ovate to suborbicular, 10-18 cm. long, 

 rounded at the apex, cordate at tlie base, finally reticulated ; petioles stout, densely tomen- 

 tose ; peduncle wanting : pedicel .short, stout : hypanthium densely tomentose and yellow- 

 ish green without : calyx abruptly bent above tlie ovary and contracted into a slender neck 

 above the inflation, the limb expanded, 3-lobed, greenish purple, dark brown in the center, 

 glabrous within : capsules cylindric-prismatic, 4-6 cm. long. 



In woods, Missouri to the Indian Territory, North Carolina and Florida. Spring and summer. 



PiPEVINE. 



7. Aristolochia macrophylla Lam. A twining vine with a stem sometimes 10 m. 

 long and minutely pubescent or almost glabrous foliage. Leaf-blades thin, reniform, sub- 

 orbicular or broadly ovate, 5-25 cm. in diameter, abruptly acute or obtuse, glabrous above. 



