664 ASCLEPIADACEAE (MILKWEED FAMILY) 



stamens, each containing an incurved horn. Stamens 5, inserted on the base 

 of the corolla ; filaments united into a tube which incloses the pistil ; anthers 

 adherent to the stigma, each with 2 vertical cells, tipped with a membranaceous 

 appendage, each cell containing a flattened pear-shaped and waxy pollen-mass ; 

 the two contiguous pollen-masses of adjacent anthers, forming pairs which hang 

 by a slender prolongation of their summits from 5 cloven glands that grow on 

 the angles of the stigma (extricated from the cells by insects, and directing 

 copious pollen-tubes into the point where the stigma joins the apex of the style). 

 Ovaries 2, tapering into very short styles ; the large depressed 5-angled fleshy 

 stigmatic disk common to the two. Follicles 2, one of them often abortive, soft, 

 ovoid or lanceolate. Seeds anatropous, flat, margined, bearing a tuft of long 

 silky hairs (coma) at the hilum, downwardly imbricated all over the large 

 placenta, which separates from the suture at maturity. Embryo large, with 

 broad foliaceous cotyledons in thin albumen. Perennial herbs ; peduncles 

 terminal or lateral and between the usually opposite petioles, bearing simple 

 many-flowered umbels, in summer. (The Greek name of Aesculapius, to whom 

 the genus is dedicated.) 



1. Anther-wings broadest and usually angulate-truncate and salient at base; 



horn conspicuous. 



* Flowers orange-color; leaves mostly scattered; juice not milky. 



1. A. tuberbsa L. (BUTTERFLY-WEED, PLEURISY-ROOT.) Roughish-hairy, 

 3-9 dm. high ; stems ascending or decumbent, very leafy, branching at the 

 summit, and bearing umbels in a terminal corymb, or scattered in racemes along 

 the branches ; leaves from linear to oblong-ovate, sessile or slightly petioled ; 

 divisions of the corolla oblong, greenish-orange ; hoods narrowly oblong, bright 

 orange, scarcely longer than the nearly erect and slender awl-shaped horns ; 

 pods hoary, erect on deflexed pedicels. (Including A. decumbens L.) Dry fields 

 and banks, N. H. to Ont., Minn., south w. and south westw. June-Aug. 



* * Corolla bright red or purple; follicles naked, fusiform, erect on the deflexed 

 pedicels (except in no. 5); leaves opposite, mostly broad. 



- Flowers rather large; hoods about 6 mm. long and exceeding the anthers ; 

 leaves transversely veined. 



2. A. lanceolate Walt. Glabrous ; stem slender, 6-15 dm. high ; leaves 

 elongated-lanceolate or linear, 1-2 dm. long, tapering to both ends, slightly 

 petioled; umbels 5-12-flowered ; divisions of the red corolla narrowly oblong; 

 the bright orange hoods broadly oblong, obtuse, much exceeding the incurved 

 horn. (A. paupercula Michx.) Wet pine barrens on the coast, N. J. to Fla. 

 and Tex. July. 



3. A. rubra L. Glabrous; leaves ovate or lanceolate and tapering from a 

 rounded or heart-shaped base to a very acute point, sessile or nearly so, 0.6-1.8 

 dm. long, 1-6.5 cm. wide, bright green; umbels many-flowered; divisions of 

 the corolla and hoods oblong-lanceolate, purple-red; the horn long and slender, 

 straightish. Wet pine barrens, etc., N. J. and Pa. to Fla., La., and Mo. July. 



4. A. purpurascens L. (PURPLE M.) Stem rather slender, 1 m. or less 

 high ; leaves elliptical or ovate-oblong, the upper taper-pointed, minutely velvety- 

 downy underneath, smooth above, contracted at base into a short petiole ; pedicels 

 shorter than the peduncle, 3-4 times the length of the dark purple lanceolate- 

 ovate divisions of the corolla ; hoods oblong, abruptly narrowed above ; the horn 

 broadly scythe-shaped, icith a narrow and abruptly inflexed horizontal point. 

 Dry ground, N. H. to Ont., Minn., Kan., and southw. Flowers 1.5 cm. long. 

 June, July. 



- - Flowers small; hoods 2-3 mm. long, equaling the anthers; veins 



ascending. 



6. A incarnata L. (SWAMP M.) Smooth or nearly so ; the stem 6-10 dm. 

 high, very leafy, with two downy lines above and on the branches of the pedun- 

 cles ; leaves oblong-lanceolate, acute or pointed, obtuse, obscurely heart-shaped or 

 narrowed at base ; flowers rose-purple (rarely whitish) ; hoods scarcely equaling 



