369 
ASCLEPIADACE.2B. (MILKWEED FAMILY.) 
pods veiny, smooth. — Varies with the leaves a little heart-shaped at 
the base, and, in var. ptJlchra, with broader and shorter-petioled 
leaves, more or less hairy as well as the stem. (A. pulchra, Willd.)— 
Wet grounds; the smooth form very common northward; the hairy 
var. southward. July, Aug. — Plant 2° -3° high, very leafy; the 
milky juice scanty. 
■*“ Leaves alternate-scattered , or the lowest opposite : juice not milky. 
11- A. ttlbcrosa, L. (Butterfly-weed. Pleurisy-root.) 
Roughish-hairy; stems erect or ascending, very leafy, usually divari¬ 
cately branching at the summit, and bearing the umbels in a terminal 
corymb; leaves varying from linear to oblong-lanceolate, sessile or 
slightly petioled; divisions of the corolla ovate-oblong (greenish-or¬ 
ange) j hoods of the crown narrowly oblong, bright orange, scarcely 
longer than the nearly erect and slender awl-shaped horns; pods 
hoary. (A. dechmbens, L .) — Dry hills and fields, common, espe¬ 
cially southward. July-Sept. — Plant l°-2° high, leafy to the sum¬ 
mit, usually with numerous corymbed short-peduncled umbels of very 
showy flowers, which are rather smaller than in No. 1. Root thick 
and fleshy, as in most species. 
— — Leaves nearly all whorled , crowded. 
12. A. vertfcillata, L. (Whorled Milkweed.) Smooth- 
ish; stems slender, simple or sparingly branched, minutely hoary in 
lines, very leafy to the summit; leaves very narrowly linear, with rev¬ 
olute margins; umbels small, lateral and terminal; divisions of the 
corolla ovate (greenish-white); hoods of the crown roundish-oval, 
about half the length of the incurved hooked-claw-shaped horns; 
pods very smooth. — Dry hills, from New England to Wisconsin, es¬ 
pecially southward. July-Sept. — Leaves 2'-3 f long, scarcely D* 
wide, 3 - 6 in a whorl, or the lowest and uppermost nearly opposite. 
Flowers small. 
2 • ACERATES, Ell. Green Milkweed. 
Nearly as in Aselepias; but the pollen-masses more slender, 
with longer stalks, and the concave upright hoods of the crown 
destitute of a horn ; whence the name, from a privative , and 
tcepas, -arof, a horn. 
1. A. vil'idiflora, EH. (Green-flowered Milkweed.) 
Downy-hoary ; stems low and stout , ascending; leaves varying from 
oval or obovate to lanceolate or almost linear, slightly petioled, mu- 
cronate-acute or obtuse, thick, at length smoothish; umbels nearly 
sessile , densely many-flowered, globose , lateral; divisions of the co¬ 
rolla oblong; hoods of the crown oblongs strictly erect, sessile at the 
base of the tube of filaments, shorter than the anthers; pods nearly 
smooth. (Aselepias viridifldra, Pursh. A. lanceolata, Ives. A. obo- 
