102 ASCLEPIADACE^E. Vlncetoxicum. 



length of the corolla-lobes, surpassing the column under the anthers : terminal membrane 

 of the latter oblong, longer than their cells, slightly surpassed by the slender columnar 

 entire beak to the stigma: young follicle tapering from the base. Proc. Am. Acad. xii. 

 73. Metastelma ? angustifolia, Torr. Bot. Mex. Bound. 159. Ravine at Santa Cruz, 

 Sonora, near the southern boundary of Arizona, Wright. Corolla a line long, smooth 

 within, except a minute and apparently glandular tuft at the base of the midrib, and the 

 obscurely puberulent recurved tips ; the sides below narrowly but distinctly convolute- 

 overlapping in aestivation. Scales of the crown wholly separate, inserted at the junction 

 of the corolla with the column. 



14. VINCETOXICUM, Mcench. (Old herbalist name of the typical 

 species, from vinceus, that which serves for binding, and toxicum, a poison, i. e. 

 poisonous bindweed.) -- Herbaceous perennial or under-shrubby plants (of the 

 Old and New Worlds) ; with twining or erect stems, mostly opposite leaves, and 

 small or minute flowers, usually dull-colored. A polymorphous and rather loosely 

 denned genus, as extended in Benth. & Hook. Gen. ii. 761 ; the indigenous North 

 American (and most other American) species forming a distinct subgenus. 



1. SEUTERA. Crown of 5 thin or thinnish scales or processes, either dis- 

 tinct or barely united at base : corolla-lobes narrowly or sometimes obscurely 

 overlapping. Lyonia, Ell., not Nutt., but rather earlier. Setitera, Reichenb. 

 Consp. 131. Amphistelma, Griseb. 



V. palustre. Stems filiform, herbaceous, freely twining upon rushes and saline grasses : 

 leaves linear, acute, fleshy (an inch or two long, a line or two wide) : peduncles longer than 

 the leaves, umbellately several-many-flowered : corolla greenish, with ovate-lanceolate 

 acuminate lobes nearly 2 lines long : scales of the crown oblong-obovate, retusc or emar- 

 ginate, nearly half the length of the corolla, slightly surpassing the deeply sagittate-based 

 anthers, distinct or very nearly so : stigma with obtusely conical apex. Ceropegia palustris, 

 Pursh, Fl. i. 184. Li/oni<i marltima, Ell. Sk. i. 316. Cynanchwn angustifolium, Nutt. Gen. 

 i. 164. Sr-ntcra man'tima, Decaisne in DC. 1. c. 590. Amji/i/xt</iitn n/i/i.-K/m/ii, C. Wright in 

 Griseb. Cat. Cubens. 175. Salt marshes along the coast from North Carolina to Texas: 

 fl. summer. (W. Ind.) 



V. SCOparium. Stems filiform, much branched, ligneous below, the branches diffuse and 

 more or less twining, becoming leafless and rush-like : leaves slender-linear, thin, very 

 acute: umbels sessile and few-flowered: flowers very small (only a line long), greenish : 

 corolla-lobes lanceolate, almost valvate in the bud: scales of the crown much shorter than 

 the anthers, ovate, hardly united at base. Cynanchum scoparium, Nutt. in Am. Jour. Sci. 

 v. (1822) 291. Cynoctonum ? scoparium, Chapm. Fl. 367. A mphistelma Jilifonne, Griseb. Fl. 

 W. Ind. 418. ^4. ephedroides & graminifolium (probably), Griseb. Cat. Cubens. 174. Meta- 

 stelma filiformc, C. Wright, in Sauvalle, Fl. Cubana, 120. Dry soil, E. Florida. (W. Ind., 

 Mex. i) 



2. VINCETOXICUM proper. Crown more fleshy and cup-like, almost entire, 

 lobed, or sometimes 5-parted: stems erect or feebly twining. 



V. NIGRUM, Mcench, of Europe, with feebly twining stems, ovate acute leaves, and peduncled 

 cymes of blackish-purple flowers (3 or 4 lines in diameter), the saucer-shaped crown cre- 

 nately 5-lobed and with obscure interposed dcnticulations sparingly occurs as a weed in 

 and near gardens, New England* to Penn., but does not deserve a place in our flora. 



15. G-ONOLOBUS, Michx. (Formed of j'con', angle, and Aop'os", pod, one 

 of the original species having costate-angled follicles.) Perennial herbs, or in 

 warmer regions shrubby (all American) ; with twining or trailing stems, usually 

 cordate opposite leaves, and mostly umbellate cymes or small fascicles of dull or 

 dark-colored flowers, produced in summer, succeeded by follicles which generally 

 resemble those of Asclepias. Fl. i. 119 ; Gray, Proc. Am. Acad. xii. 73, 74. 



