ASCLEPIADACE^. (mILKWEED PAMILT.) 397 



1- ■<- ■<- Stem perfectly simple, producing only a single conspicuously-peduncled termi- 

 nal umbel of dull-colored largish (6" long) flowers : hoods and lobes of the co- 

 rolla broad : pods smooth : whole plant glabrous or nearly so, and pale or glau- 

 cous ! leaves closely sessile, transversely veiny. 



10. A. ObtUSifdlia, Michx. Stemta.ll{2°-3°high); leaves wavy, oblong 

 with a heart-shaped clasping base, very obtuse or retuse (2^'- 5' long) ; peduncle 

 3' -12' long; corolla pale greenish purple; hoods of the crown truncate and 

 somewhat toothed at the summit, shorter than the slender awl-pointed horn. — 

 Sandy woods and fields : not rare, especially southward. 



11. A. Me^dil, Torr. (in Ed. 2, addend.) Stem slender (l°-2o high) ; 

 leaves ovate or oblong-ovaie, not wavy, obtuse or acutish (1J'-2J' long) ; peduncle 

 only twice the length of the upper leaves ; pedicels rather short ; corolla green- 

 ish-white ; hoods of the crown rounded-truncate at summit, and with a sharp 

 tooth at each margin, somewhat exceeding the stouter horn ; pod unknown. — 

 Augusta, DUnois, Dr. S. B. Mead. Clinton, Iowa, Dr. Vasey. June. 



■<-■'- -1- 1- Stem simple or mostly so (2° -4° high), bearing 2-5 panicled umbels on 

 a naked terminal peduncle, and sometimes single axillary ones : flowers pink-red, 

 rather large {over 6" long) : crown conspicuously elevated above the base of the 

 cmoUa : pods smooth : whole plant glabrous or nearly so. 



12. A. rtlbra, L. Leaves ovate or lanceolate and tapering from a rounded or 

 heart-shaped base to a very acute point, sessile or nearly so (2'-6' long, ^'-2J' 

 wide), bright green ; umbels many-flowered ; divisions of the corolla and hoods 

 of the crown oblong-lanceolate, purple-red ; the horn long and slender. ( A. lauri- 

 folia, Michx. A. acuminata, Pursh.) — Wet pine-barrens, &c.. New Jersey and 

 Penn. to Virginia and southward. 



13. A. paup^rcUla, Michx. Stem slender (2° -4° high); leaves elon- 

 gated lanceolate or linear (.5' - 10' long), tapering to both ends, slightly petioled ; 

 umbels 5 - 12-flowered ; divisions of the red corolla narrowly oblong ; the bright orange 

 hoods broadly oblong, obtuse, much exceeding the incurved horn. — Wet pine-bar- 

 rens on the coast. New Jersey, Virginia, and southward. 



* * Leaves scattered, or some opposite: milky juice little or none: flowers orange-red. 



14. A. tuberbsa, L. (Butterfly-weed. Pletjeist-eoot.) Eough- 

 ish-hairy ; stems erect or ascending, very leafy, 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 oblong (greenish- 

 orange ) ; hoods of the crown narrowly oblong, bright orange, scarcely longer 

 than the nearly erect and slender awl-shaped horns ; pods hoary. (A. decum- 

 bcns, i.) — Dry hills and fields: common, especially southward. — Plant 1°- 

 2° hij;h, leafy to the summit, usually with numerous and corymbed short- 

 peduncled umbels of showy flowers. 



* 5(t * Leaves nearly all whorled, rarely alternate, crowded: flowers white, small. 



15. A. verticillkta, L. (Whoeled M.) Smoothish; stems slender, 

 simple or sparingly branched, very leafy to the summit ; leaves very narrowly 

 linear, with revolute margins (2'-3' long, 1" wide), 3-6 in a whorl; umbels 

 small, lateral and terminal ; divisions of the corolla ovate (greenish-white) ; 



