A SCL EPIA D A CEA E. 743 



10-15 cm. long. In dry fields, mostly in sandy soil, Me. to Fla., Minn., Kans. and 

 Tex. May- Aug. [A. obtusi folia Michx.] 



11. Asclepias Meadii Torr. MEAD'S MILKWEED. (I. F. f. 2910.) Nearly 

 glabrous throughout, pale green or glaucous; stem simple, or rarely branched 

 above, 3-6 dm. high. Leaves flat, mostly distant, ovate, ovate-lanceolate, lanceo- 

 late or the lower oblong, the margins scabrous ; umbel several-flowered, borne on a 

 peduncle 8-15 cm. long; corolla-segments greenish yellow, ovate, acute, 6-9 mm. 

 long; hoods ovate, purplish, nearly twice as long as the anthers, rounded and 

 truncate at the summit, longer than the subulate inflexed horn, with'a small tooth 

 at each side on the inner infolded .margin; follicles erect on decurved pedicels, 

 puberulent, narrow, 10-12 cm. long. Dry soil, 111. to Iowa and Wise. June-Aug. 



12. Asclepias exaltata (L.)Muhl. POKE OR TALL MILKWEED. (I. F. f. 

 2911.) Nearly glabrous throughout, with two opposite lines of pubescence on the 

 usually simple stem, 1-2 m. high. Leaves thin or membranous, oval, ovate or 

 oblong, acuminate at both ends, 10-23 cm - l n g> 3~ 10 cm - wide, the lower some- 

 times obovate, obtuse, shorter; peduncles 2.5-8 cm. long; umbels usually several; 

 pedicels slender, drooping or spreading, 2.5-5 cm. long, puberulent; corolla-seg- 

 ments ovate or oblong, obtusish, 6-9 mm. long; hoods white or pink, slightly- 

 shorter than the anthers, much shorter than the subulate horn, at the summit 

 truncate and entire or erose, with I or 2 slender teeth on each of the inner mar- 

 gins; follicles erect on the deflexed pedicels, downy, long-acuminate, 10-15 cm. 

 long. In thickets and woods, Me. to Minn., Ga. and Mo. June-Aug. 



13. Asclepias variegata L. WHITE MILKWEED. (I. F. f. 2912.) Stem 

 glabrous below, pubescent above when young, simple, 3-9 dm. high. Leaves 

 thick, oval, ovate, oblong or the lower somewhat obovate, obtuse and cuspidate or 

 acutish, dark green above, pale beneath, 6-15 cm. long, the middle ones sometimes 

 verticillate in 4/3; petioles 6-25 mm. long; umbels 1-4, terminal, or rarely I or 2 in 

 the upper axils, densely many-flowered; pedicels erect or ascending, usually 

 densely puberulent; corolla segments ovate or oval, about 6 mm. long, white, or 

 purple near the base; column purplish; hoods globose-obovoid, obtuse, spreading, 

 longer than the anthers, about equalling the semi lunate horizontally pointed 

 horn; follicles downy, erect on the deflexed fruiting pedicels, 10-13 cm. long. In 

 dry woods and thickets, Conn, to 111., Fla., Ark. and La. June-July. 



' 14. Asclepias quadrifolia Jacq. FOUR-LEAVED MILKWEED. (I. F. f. 2913.) 

 Stem slender, simple, 3-6 dm. high, usually leafless below. Leaves thin, spar- 

 ingly pubescent on the veins beneath, ovate to lanceolate, 5-15 cm. long, acute or 

 acuminate, or the lowest pair much smaller, obovate and obtuse; umbels I 4, ter- 

 minal, or rarely in the upper axils; peduncles slender; corolla- lobes lanceolate- 

 oblong, 4-6 mm. long; hoods white, obtuse at the apex, broadly 2-toothed above ihe 

 base, twice as long as the anthers and the incurved horn; follicles erect on the 

 erect fruiting pedicels, 8-13 cm. long, glabrous. Woods and thickets, Me. and 

 Ont. to Minn., N. Car. and Ark. May-July. 



15. Asclepias Syriaca L. COMMON MILKWEED. SILKWEED. (I. F. f. 

 2914.) Stem stout, usually simple, 9-15 dm. high, finely pubescent at least above. 

 Leaves oblong, oval or ovate, densely pubescent beneath, soon glabrous above, 10- 

 23 cm. long, the primary nerves wide-spreading; petioles stout, 6-17 mm. long; 

 umbels several or numerous; peduncles pubescent or tomentose, 3-9 cm. long; 

 pedicels 2.5-5 cm - l n gi corolla green-purple, its segments oblong-lanceolate, 6-9 

 mm. long; hoods ovate-lanceolate with a tooth on each side, longer than the anthers 

 and the incurved horn; follicles 6-13 cm. long, ereot on recurved pedicels. In 

 fields and waste places, N. B. to the N. W. Terr., N. Car. and Kans. Leaves 

 rarely lanceolate. June-Aug. [A- Cor nut i Dec.] 



16. Asclepias speciosa Torr. SHOWY MILKWEED. (I. F. f. 2915.) White- 

 tomentose or canescent all over, or glabrate below, pale; stem simple, stout, 37 

 dm. high. Leaves thick, broadly ovate or oval, petioled, 8-20 cm. long; pedun- 

 cles 2.5-7 cm. long; umbels several or rarely solitary, many-flowered; pedicels 

 stout; corolla purple- green, its segments oblong or ovate-oblong, 913 mm. long, 

 tomentose on the outer face; column very short or none; hoods lanceolate, 11-15 

 mm. long, obtusish, expanded and with 2 blunt teeth below, the apex ligulate, 5-7 

 times as long as the anthers; horn short, inflexed; follicles erect or spreading on 



