ASCLEPIADACE^. (mILKAVEED FAMILY.) 365 



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

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

 small, tiie 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. — Stenx 2° - 3° high. 

 Leaves l'-2' long. Follicle smooth. 



4- -(— H— H— -t— 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 

 brigiit orange, erect, oblong-lanceolate, twice as long as tlie gynostegium, and 

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

 and July. — Stem \°-2° long. 



1 8. A. Michauxii, Uecaisne. 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. longifolia, 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 shrulihi/ : seeds mostli/ 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, .1//c/i.r.) — Muddy banks of rivers, Florida to South Caro- 

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



2. ACERATES, Ell. 



LeaA'cs of the crown destitute of a horn-like appendage. Otherwise like 

 Asclepias. 



* Leaves opposite. 



1- A. viridiflora, Ell. Pubescent; stem stout, simple; leaves varj'ing 

 from oval or obovatc to lanceolate, acute, obtuse, or emarginate, nndtilatc, 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 U'-2i' 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* 



