^sclepias. ASGLEPIADACEJE. 91 



as to Hort. Cliff. ; Michx. 1. c. A. pvlchra, Ehrhart ; Sweet, Brit. Fl. Gard. ser. 2 t. 18 — 

 With the smooth form. ' 



Var. longifolia. Leaves elongated- or linear-lanceolate, 4 to 7 inches long a third 

 to half inch wide, glabrous or with minute pubescence : stems 4 to 6 feet high :' flowers 

 paler. — ^. tuberosa, Torr. in Pacif. K. Rep. vii. 18. — Texas to New Mexico. 



* nr cf ^"™"^ t"^\ T^^ greenish, yellowish, white, or merely purplish-tinged: leaves opposite 

 or sometimes whorled, or the upper rarely alternate or scattered. "^ " ^ i l'"'*"" 



H- Follicles echinate with soft spinous processes and denselv tomentose, large (3 to 5 inches lone) 

 ancl ventricose. ovate and acuminate, arrect on deflexed pedicels: leaves large and broad short- 

 petioled, transversely veined: stems stout and simple, 2 to 5 feet high. 

 A. speciosa, Torr. Finely canescent-tomentose, rarely glabrate with age : leaves from 

 subcordate-oval to oblong, thickish : peduncles shorter than the leaves : pedicels of the 

 many-flowered dense umbel and the calyx densely tomentose : flowers purplish large • 

 corolla-lobes ovate-oblong, 4 or 5 lines long : hoods 5 or 6 lines long, spreading, the dilated 

 body and its short inflexed horn not surpassing the anthers, but the centre of its truncate 

 summit abruptly produced into a lanceolate-ligulate thrice longer termination: column 

 hardly any : wings of the anthers notched and obscurely corniculate at base. — Ann. Lye. 

 N. Y. ii. 218. A. Douylasii, Hook. Fl. ii. 53, t. 142, & Bot. Mag. t. 4413. — Along streams, 

 Nebraska to Arkansas, and west to S. Utah, California, and Washington Territory. 

 A. Cornuti, Decaisne. (Common Milkweed.) Finely soft-pubescent or tomentulose • 

 leaves green and early glabrate above, oval or oblong, obtuse or roundish at base: pe- 

 duncles little longer than the very numerous pubescent pedicels : corolla dull purple or 

 greenish-purple, rarely almost white ; the lobes ovate, three or four lines long : hoods 

 whitish, ovate, rather longer than the anthers, with a tooth on each side below the middle ; 

 the subulate horn short and incurved : column short. — Prodr. 1. c. 564 ; Torr. Fl. N. y! 

 ii. 119. A. Syriaca, L. (Cornuti, Canad. t. 90) ; Spenner in Nees Gen. Germ. fasc. 21, t. 1-3.' 

 — Canada to Saskatchewan and N. Carolina, chiefly in fields. 



-1- -1- Follicles minutely warty-echinate along the tapering apex, otherwise as in the succeeding: 

 wings of the anthers emarginately bicorniculate at base. 

 A. Sullivantii, Engelm. Glabrous throughout, a yard high, leafy to the top : leaves 

 opposite, thickish, oblong, with subcordate or rounded base, nearly sessile (4 or 5 inches 

 long) : umbels terminal and from the uppermost axils, short-peduncled, rather many- 

 flowered: flowers flesh-colored: corolla-lobes oval, 5 lines long: column short: hoods 

 oval, with a gibbosity on each side near the base, almost truncate at summit, a third 

 longer than the anthers ; the falcate-subulate horn rising from near the base, horizontally 

 and slightly exserted from the middle. — Gray, Man. ed. 1, 366, ed. 5, 395. — Low grounds, 

 Ohio (Sullivant) to Kansas (Freviont). Follicle 3 to 5 inches long, ovate-lanceolate, nearly 

 glabrous, smooth, except small and soft conical warty processes scattered along the beak. 



•f- -f- -1- Follicles wholly unarmed and smooth throughout, either glabrous or tomentulose-pubes- 

 cent. ^ 



++ Arrect or ascending on the deflexed or decurved fructiferous pedicels. 



== Umbel solitary on the perfectly simple strict stem, elevated on a naked terminal peduncle: 

 leaves all closely sessile, broad, transversely veined : plant glabrous and pale or glaucous : follicles 

 fusiform : anthers either bicorniculate or salient-angled at base of the wing. 



A. Obtusifolia, Michx. Stem 2 or 3 feet high : leaves undulate, oblong or elliptical, 

 3 to 5 inches long, with rounded or refuse apex and cordate-clasping base : peduncle 2 to 

 12 inches long: umbel loosely many-flowered: corolla dull greenish-purple; the lobes 

 oblong, 4 lines long : column as high as broad : hoods flesh-color, erosely truncate and 

 somewhat toothed at the broad summit, hardly exceeding the anthers, shorter than the 

 falcate-subulate incurved horn : anther-wings bicorniculate at base in the manner of A. 

 Sullivantii. — Fl. i. 113; Decaisne, I.e. 565. A. purpurascens, Walt. Car. 103. — Dry or 

 sandy soil. New England to Florida, Texas, and Nebraska. 



A. Meadii, Torr. A foot or two high : leaves plane and even, ovate-lanceolate, or 

 rarely lanceolate, obtuse or acute, rounded at the sessile base, rough-margined, 1^ to 3 

 inches long : peduncle 2 to 4 inches long : umbel 6-20-flowered : corolla greenish-yellow ; 

 the lobes ovate, 3 or 4 lines long : column very short : hoods purplish, with rounded-trun- 

 cate entire summit and a tooth at the inner margins, exceeding the anthers and the subu- 

 late inflexed horn : anther-wings with entire but descending salient angle at base. — Gray, 

 Man. ed. 2, addend. 704, ed. 5, 397. — Dry ground, Illinois, 5. B. Mead, Iowa, Vasey, &c. 



