ASCLEPIAS. 



ASCLEPIADACEiE. 



123 



ft Leaves alternate or verticillale. 



8. Asclepias tuberosa, jLw. Pleurisy-root. Butterfly-weed. 



Hairy ; stem erect, oblique or decumbent, with spreading or often recurved branches ; 

 leaves varying from oblong-lanceolate to linear-lanceolate or linear, mostly alternate, on very 

 short petioles ; umbels numerous, often corymbose ; lobes of the crown lanceolate-oblong ; 

 horn subulate, rather erect. — Linn. sp. (ed. 2.) 1. p. 316 ; Michx. fl. 1. p. 117 ; Pursh, 

 ft. 1. p. 183 ; Bigel. med. bot. 2. p. 89. t. 6, and fl. Bost. p. 100 ; Ell. sk. I, p. 325; Bart, 

 veg. mat. med. 1. t, 22 ; Torr. fl. 1. p. 285 ; Beck, bot. p. 237 ; Sweet, Brit.fl. gard. (ser. 

 2.) t. 24 ; Darlingt. fl. Cest. p. 173 ; Decaisne in DC. prodr. 8. p. 567. A. decumbens, 

 Linn. sp. (ed. 1.) 1. p. 216. 



Plant destitute of a milky juice. Root large and fleshy, branching or fusiform. Stems 

 commonly numerous, usually ascending or procumbent, 1-2 feet long. Leaves mostly 

 scattered, but sometimes (particularly the lower ones) opposite, 2-4 inches long and half an 

 inch to an inch wide, acute or rather obtuse : petioles about two lines long. Umbels many- 

 flowered. Flowers bright orange. Lobes of the crown about twice as long as the stigma, 

 erect : horn about as long as the lobe. Tube of the stamens contracted into a narrow neck 

 under the crown. Follicles lanceolate, acuminate, about four inches long. 



Sandy fields ; frequent. July - August. This species has long been celebrated for its 

 medicinal virtues, but its use is now almost confined to the Botanic doctors. Jt is considered 

 diaphoretic, cathartic and expectorant. (See the works quoted above, and Wood <§• Bache's 

 U. S. Dispens. p. 118.) 



9. Asclepias verticillata, Linn. (PI. LXXXVII.) Whorled Silkweed. 



Stem simple or branched, marked with pubescent lines, slender ; leaves mostly verticillate, 

 narrowly linear, revolute on the margin ; umbels lateral and terminal ; lobes of the crown 

 short, very obtuse, 2-toothed ; horns falcate, much exserted. — Linn. sp. 1. p. 217 ; Michx. 

 fl. 1. p. 116 ; Pursh, fl. 1. p. 183 ; Ell. sk. 1. p. 324; Nutt. gen. 1. p. 168 ; Bigel. fl. 

 Bost. p. 104 ; Torr. fl. I. p. 284 ; Beck, bot. p. 236 ; Darlingt. fl. Cest. p. 173 ; Hook, 

 fl. Bor.-Am. 2. p. 54. I. 144 ; Decaisne in DC. prodr. 8. p. 569. 



Stem 1-3 feet high, marked with 4-6 downy lines, very slender, usually more or less 

 branched towards the summit. Leaves 2-3 inches long and about one line wide, crowded, 

 more or less perfectly verticillate, but often scattered ; the margin narrowly revolute. Umbels 

 about an inch in diameter : peduncle about half an inch long, and the pedicels about the same 

 length. Flowers small. Corolla greenish white. Stamineal crown white, elevated on the 

 contracted tube of the stamens : lobes almost equalling the stigma, concavely truncate, with 

 a large acute tooth on each side. Follicles about two inches long, linear-lanceolate, tapering 

 to a long point, smooth. 



Dry hill-sides ; frequent. July - September. 



16* 



