148 ASCLEPIADACEAE. 



1. P. clausa (Jaeq.) Vail. Leaf -blades 3-S cm. long, ovate-oblong to oblong- 

 lanceolate, rounded or siibcordate at the base: peduncles twice as long as the 

 leaves or more : calvx-lobes oblong-lanceolate : corolla white ; lobes oblong Lo 

 ovate, 4-5 mm. long: follicles 5-7 cm. long: seeds about 3 mm. long. — Coastal 

 hammocks. F. K. {Bah., Cuha, Ant.) 



2. ACERATES Ell. Erect or spreading herbs, with narrow or relatively 

 narrow leaf -blades. Calyx-lobes 5. Corolla rotate: lobes reflexed. Crown- 

 hoods approximate to the anthers, the column very short or stout. 



1. A. floridana (Lam.) A. Hitchc. Plants 3-8 dm. tall or more, green: leaf- 

 blades linear to elongate linear-lanceolate, 7-16 cm. long: corolla-lobes 3-3.5 

 mm. long: hoods about 2 mm. long: anther-wings 1.5-2 mm. long: pollinia- 

 bodies nearly 1 mm. long: seed-coma 3-4 cm. long. — Everglades. — Greex- 



MILKWEED. 



3. ASCLEPIAS [Tourn.] L. Erect or spreading herbs, with narrow or 

 broad leaf -blades. Calyx-lobes 5. Corolla rotate: lobes reflexed. Crown- 

 hoods approximate to the anthers, or nearly so, not adnate to the anther- 

 column, the horn mainly adnate only at the base of the hood. Anther-wings 

 salient at the base. Pollinia longer than the caudieles. — Milkweed. 



Follicles erect on deflexed pedicels : horn not longer than the hood : flowers orange- 

 yellow. 

 Hoods 6-7 mm. long : leaf-blades truncate or cordate at the base. 



1. A. Rolf sit. 

 Hoods 3^ mm. long : leaf-blades tapering at the base. -. A. lanceolata. 



Follicles erect on erect pedicels : horn long-exserted : flowers 



greenish-white. 3. A. verticillata. 



1. A. Rolfsii Britton. Stems erect or ascending, 1-3 dm. tall, hirsute: leaf- 

 blades mainly oblong, sometimes narrowly so, when broad sometimes fiddle- 

 shaped, 3-7 cm. long, truncate or cordate at the base : corolla-lobes oblong, 6-7 

 mm. long: horn arising below the hood-auricles. — Pinelands. 



2. A. lanceolata Walt. Stems 4-11 dm. tall, glabrous or nearly so: leaves few, 

 distant; blades elongate-linear, linear-lanceolate, or narrowly lanceolate, mostly 

 1-2 dm. long, narrow at the base: corolla-lobes oblong, 8-9 mm. long: horn 

 arising from the base of the hood. — Everglades. 



3. A. verticillata L. Stems 3-8 dm. tall, commonly pubescent in lines: 

 leaves numerous, close; blades narrowly linear to linear-filiform, 2-6 cm. long: 

 corolla-loVjes greenish-white, 3-4 mm. long: hoods about 1 mm. long, about 

 equalling the androecium or shorter, with erect auricles within; horn slender, 

 much exceeding the hood: column about 1 mm. long. — Pinelands. 



4. ASCLEPIADORA A. Gray. Spreading herbs with alternate leaves. 

 Calyx-lobes 5, spreading. Corolla rotate: lobes spreading. Crown-hoods invo- 

 lute and hooded at the apex, with an internal ridge above the middle. Anthers 

 ecjualling the gynostegium: wings rounded at the base. Pollinia with caudieles 

 nearly as long as the narrow bodies. 



1. A. viridis (Walt.) A. Gray. Stem 2-6 dm. long, stout: leaf-blades oblong 

 to lanceolate, 6-10 cm. long, rather thin: calyx-lobes about 4 mm. long, cilio- 

 late: corolla-lobes greenish, 10-11 mm. long: hoods about 4.5 mm. long, pur- 

 plish or violet: anther-wings 2.5 mm. long: follicles 6-11 cm. long. — Pinelands. 

 — F. K. 



5. AMPHISTELMA Gristh. 81en<ler vines with narrow leaf-blades. 

 Calyx-lobes longer than the corolla-tube. Corolla rotate-campanulate: lobes 



