ORDER 97.—ASCLEPIADS. 273 
by the middle. Follicles long, slen- 
der, separate. Seeds with a tuft of 
long, silky down. June-August. 
1 A. androsemifo’lium. Tutsan-leaved D. 
Corolla rose-white, much longer than 
the calyx. Leaves ovate. Plant 
smooth, elegant, about 3f. high. 
2 A.cannabi’num. Hemp D, Cor. green- 
ish-white, scarce longer than the 
calyx. Leaves oblong. Bark tough 
as hemp. 
Fig. 620. Common Dog’s-bane, 1. A flower 
of the natural size, 2. The flower cut open, 
showing the peculiar stamens. 3. The 2 styles 
and stigmas. 4. The plan of tne flower. 5. The 
2 follicles. 6, A seed with its tuft of silk. 
Orper XCVII. ASCLEPIADACEA. Asclepiads. 
Plants (chiefly herds in the United States) with a milky juice ; 
leaves opposite (rarely whorled or scattered), entire, without stipules; 
Jlowers generally umbeled, 5-parted, regular; sepals and also the 
petals united at base, both commonly valvate in the bud; 
stamens united into a fleshy mass with the two stigmas; 
pollen cohering in masses; ovaries 2, forming follicles in fruit 
Analysis of the Genera. 
§ Plants erect. Stamen-mass crowned with 5 little hoods....2 
§ Plants twining or prostrate....3 
2 Hoods each with a little projecting horn....a 
2 Hoods destitute of horns....b 
8 Flowers dark purple....¢ 
8 Flowers whitish or flesh-colored.... 
a Petals reflexed. Hoods erect, horns incurved. Silkgrass. Milkweed. Ascie’rias. 1 
bp Petals reflexed. Hoods erect, adnate to the anthers. ACERA/TES. 
b Petals spreading, green. Hoods free from the authers. S. ANAN’THERIX. 
b Petals erect, yellowish, Mass of anthers stalked. S. Popostie’Ma, 
12* 
