asclepiadacejE. (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, tlie 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. 



1- 1— -<- ■<- -1- Leaves alternate, or the lowest opposite. 



17. A. tuberosa, 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, prosti-ate ; 

 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. longifolia, Ell., Michx. in psLrt.) 

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

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



5 2. Stem shrubby : seeds moslli/ 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. iehilis, Michx.) — Muddy banlis 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, ^''l- 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 p high. Leaves 1 J' - 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, incui-ved, twice as long as the gynosto- 



31* 



