AUISTOLOCHIACE^. (bIRTHWORT FAMILY.) 371 



Divisiox III. APETALOUS EXOGENOUS PLANTS. 



Floral envelopes single, consisting of a calyx only, or alto- 

 gether wanting. 



Order 105. ARISTOLOCHIACE7E. (Birthworx 

 Family.) 



Herbs or woody vines, with alternate petioled mostly cordate and entire 

 leaves, and solitary peduncled dull-colored flowers. — Calyx adherent to 

 the 6-celled ovary, tubular, valvate in the bud. Stamens 6-12, more or" 

 less united with the styles: anthers adnate, extrorse. Fi'uit 6-celled, few 

 - many-seeded. Seed anatropous. Embryo minute, at the base of fleshy 

 albumen. 



1. ASARUM, Tourn. Asarabacca. 



Calyx reg:ular, 3-lobetl. Stamens 12, the filaments partly united with the 

 style, and usually prolonj^ed be3'ond the anthers. Capsule fleshy, globose, open- 

 ing irregularly — Aromatic pei-ennial herbs, with creeping stems, long-i)eiiolcd 

 cordate or kidney shaped leaves, and axillary peduncled flowers. 



^ 1. AsAUL'Ji. — Cahjx hell-shaped, adnate to the ovary, 3-parted : Jilaments free or 

 itcarlif so : stigma G-lohed. — Leaves deciduous. 



1. A. Canadense, L. (Wild Ginger-root.) Pubescent ; leaves 2, kid- 

 ney-shaped; calyxdobes acuminate; filaments as long as the style. — Mountains 

 of Nortli Carolina, and northward. April and May. — Flowers short-peduncled, 

 purple within. 



§ 2. IlETEROTROrA — Culi/x inflated, nearlij free from the ovary, 3-clefl : fila- 

 vients united with the ovary : styles 6 : stiymas 2-cteft. — Leaves evergreen, smooth, 

 mottled. 



2. A. Virginieum, L. Leaves round-cordate ; calyx inflated-bell-shaped, 

 with rounded lobes ; stigmas deeply 2-cleft. — Rich shady woods in the upper 

 districts, Georgia, and northward. April and May. — Leaves single or 2-3 

 together, 2' long. Flowers 8" - 9" long, nearly sessile at the base of the petioles, 

 greenish witiiout, dull purple within. 



3. A. arifolium, Michx. Leaves oblong-cordate; calyx pitcher-shaped, 

 with rounded lobes ; stigmas slightly 2-clcft. — Shady woods in the lower dis- 

 tricts, Florida to North Carolina. March and Ajiril — Leaves 3'- 4' long, 

 auriculate at the base, long-petiolcd. Calyx 1' long, distinctly jjcduucled, con- 

 tracted above the middle, dark purple within. 



2. ARISTOLOCHIA, Tourn. Birthwort. 



Calyx tubular, commonly bont and inflated above the ovary. Anthers 6, ses- 

 sile, adnate to the 3- 6-lobed or angled stigma. Capsule 6-valved. — Erect or 



