404 NYCTAGINACE.E. (FOUR-O'CLOCK FAMILY.) 



2. ARISTOLOCHIA, Tourn. Birthwort. 



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

 at the throat. Stamens 6 ; the sessile anthers wholly adnate to the back of the 

 short and fleshy 3 - 6-lobed or angled stigma. Pod naked, 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 obtusely 

 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. Serpentciria, L. (Virginia Snakeroot.) Stems (8' -15' high) 

 branched at the base, pubescent ; leaves ovate or oblong from a heart-shaped 

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

 peduncled. — A narrow-leaved variety is A. sagittate, Muhl., A. hastata, Nutt., 

 &c. — Rich woods, Connecticut to Indiana and southward : not common except 

 near the Alleghany Mountains. July. — 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 : twining shrubs : flowers from one or two of the super- 

 posed accessory axillary buds. 



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

 brous; leaves round-kidney-shaped; peduncles with a clasping hract; calyx (lj' 

 long) with a brown-purple abrupt fat border. — Rich woods, Penn. to Kentucky, 

 and southward, along the mountains. May. — Stems sometimes 2' in diameter, 

 climbing trees: full-grown leaves 8'- 12' broad. 



3. A. tomentdsa, Sims. Downy or sofi-hairy ; leaves round-heart-shaped, 

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

 and a rugose refexed limb. — Rich woods, from S. Illinois southward. June. 



Order 83. NYCTAGINACEA2. (Four-o'clock Family.) 



Herbs (or in the tropics often shrubs or trees'), ivith mostly opposite and 

 entire leaves, stems tumid at the joints, a delicate tubular or funnel-form 

 calyx which is colored like a corolla, its persistent base constricted above the 

 1-celled 1-seedcd ovary, and indurated into a sort of nut-like pericarp ; the 

 stamens few, slender, and hypogynous ; the embryo coiled around the out- 

 side of mealy albumen, with broad foliaceous cotyledons. — Represented in 

 our gardens by the Four-o'clock, or Marvel of Peru (Mirabilis 

 Jalapa), in which the calyx is commonly mistaken for a corolla, the cup- 

 like involucre of each flower exactly imitating a calyx ; — and by a single 



1. OXYBAPHUS, Vahl. Oxybaphus. 



Flowers 1 -5 in the same 5-lobed membranaceous broad and open involucre. 

 which enlarges and is thin and reticulated in fruit. Calyx with a very short 



