ASCLEPIADACE^l. (MILKWEED FAMILY.) 365 



16. A. verticillata, L. Stem slender, branching, pubescent ; leaves 

 narrowly linear, with the margins revolute, 4-5 in a whorl ; umbels several, 

 small, the peduncle and pedicels nearly equal ; corolla greenish ; leaves of the 

 crown white, roundish, half as long as the slender incurved horn. Open woods 

 and fence-rows, Florida, and northward. July - Sept. Stem 2 - 3 high. 

 Leaves 1 ' - 2' long. Follicle smooth. 



t- (- (--<-- Leaves alternate, or the lowest opposite. 



17. A. tuber osa, L. Hirsute; stem erect or declining, widely branched 

 above, very leafy ; leaves varying from linear to oblong, acute, short-petioled ; 

 umbels numerous, corymbose ; corolla yellowish-orange ; leaves of the crown 

 bright orange, erect, oblong-lanceolate, twice as long as the gynostegium, and 

 rather longer than the slender incurved horn. Light dry soil, common. June 

 and July. Stem 1 -2 long. 



18. A. Michauxii, Decaisne. Pubescent ; stems several, short, prostrate ; 

 leaves linear, erect, the lower ones mostly opposite ; umbels 1-3, terminal, 

 sessile or peduncled ; flowers gray and purple ; leaves of the crown ovate, 

 spreading, as long as the subulate horns, and longer than the gynostegium; 

 follicle long, linear-lanceolate, tomentose. (A. angustifolia, Ell., Michx. in part.) 

 Low sandy pine barrens, Florida to South Carolina. April - May. Stems 

 6'- 12' long. Leaves 3'- 4' long. Follicle 4' -5' long. Flowers fragrant. 



2. Stem shrubby : seeds mostly naked. 



19. A. perennis, Walt. Stem branched, pubescent in lines, shrubby at 

 the base ; leaves thin, lanceolate or oblong-lanceolate, tapering at each end, 

 paler beneath; umbels 5-7, long-peduncled, pubescent, the upper ones corym- 

 bose ; corolla small, white ; leaves of the crown spreading, half as long as the 

 needle-shaped, erect horn ; follicle ovate-lanceolate, smooth. (A. parviflora, 

 Pursh. A. debilis, Michx.) Muddy banks of rivers, Florida to South Caro- 

 lina. June -Aug. Stem 1 - 2 high. Leaves 2' - 4' long. 



2. ACERATES, Ell. 



Leaves of the crown destitute of a horn-like appendage. Otherwise like 

 Asclepias. 



* Leaves opposite. 



1. A. viridiflora, Ell. Pubescent; stem stout, simple; leaves varying 

 from oval or obovate to lanceolate, acute, obtuse, or emarginate, undulate, short- 

 petioled; umbels lateral and terminal, nearly sessile, densely many-flowered; 

 flowers small, greenish ; leaves of the crown oblong, erect, as long as the sessile 

 gynostegium. Dry sterile soil, Florida, and northward. June and July. 

 Stem 1- 1| high. Leaves l'- 2$' long. 



2. A. connivens, Decaisne. Stem stout, simple, pubescent above ; .eaves 

 nearly sessile, erect, mucronate, the lower ones approximate, oblong or oblong- 

 obovate, the upper more distant, smaller and lanceolate ; umbels 3-6, 6-9- 

 flowered, the stout peduncle and pedicels nearly equal, pubescent ; flowers large, 

 greenish ; leaves of the crown oblong, incurved, twice as long as the gynoste- 



31* 



