ASCLEPIADACE^. 310 ASCLEPIAS. 



5. A. incarna'ta. 



Stem erect, branching above ; leaves lanceolate, on short petioles, slightly 

 tomentose ; umbels numerous, erect, mostly terminal, often in opposite pairs ; 

 segmeiits of the, corona entire, horns exsert. A handsome species found in 

 wet places. Stem 3 — 4 feet high, with two hairy lines. Leaves 4 — 7 inches 

 long, ^ — H inch wide, rather abrupt at base, tapering to a very acute point, 

 on petioles ^ inch long. Umbels close, 2 — 6 together at the top of the stem or 

 branches, each an inch or more in diameter, on a peduncle 2 inches long, and 

 consisting of 10 — 20 small flowers. Corolla deep purple, corona paler. 

 Horns subulate, curving inwards over the summit of the antheridium. 

 July. Per. Rose-culored Silkweed. 



j3. puJchra; stem and leaves densely tomentose, the latter elliptical-lanceo- 

 late, 3 — 4 times as long as wide, sessile or on very short, hairy stalks. Stem 

 4 — 5 feet high. A remarkable variety. 



6. A. amce'na. 



Stem simple, downy in 2 rows ; leaves subsessile, oblong-oval, pubescent 

 beneath; umbels terminal, erect; segments of the corona erect, horns exsert. 

 An elegant plant in low grounds. Stem 1 — 3 feet high. Leaves opposite, 

 large, obtuse, rather thick, with purple nerves. Umbels arise from the top of 

 the stem and often from the upper axils. Flowers bright purple, on long, 

 straight pedicels. Corona long, erect, rigid. Jl. Per. Oval-leaved Silkweed. 



7. A. quadrifo'lia. 



Stem erect, simple, smooth ; leaves smooth, thin, petiolate, ovate, acuminate, 

 mostly in 4s ; umbels few, lax, on long, terminal or a.\illary peduncles ; corona 

 long, segments 2-toothed, horns short. An elegant species in dry woods. 

 Stem about 2 feet high, slender, often with 1 — 2 hairy lines. Leaves opposite, 

 the middle or upper pairs near together so as to appear in 4s, 2 — 3 inches long 

 and half as wide, acute or acuminate, on petioles 2 — 4 inches long. Flow- 

 ers small, while, on filiform stalks with a pubescent line. Corona twice as 

 long as antheridium. July. Per. Four-leaved Silkweed. 



(i. dehilis ; stem v/eak, erect, simple; leaves large, thin, oval-lanceolate, 

 acute at each end, the 4 upper ones sometimes whorled ; ximbel terminal. 

 Grows in shades. 



* * Leaves verticillate. 



8. A. veticilla'ta. 



Stem erect, simple, marked with pubescent lines; leaves generally verticil- 

 late, very narrowly linear, revolute; segments of the corona short, 2-toothed, 

 horn falcate, exsert. A slender and delicate species, 2 feet high, in swamps 

 (dry soil, authors). Leaves in whorls of 4 — 6, 3 — 5 inches long and a line 

 in width. Flowers small, greenish white, in small, lateral umbels. Peduncles 

 half as long as the leaves. July. Per. Whorled Silkweed. 



* * * Leaves alternate. 



9. A. TUBERO'SA. 



Stem ascending, hairy, with spreading branches at top ; leaves alternate, 

 oblong-lanceolate, sessile ; umbels numerous, forming large, terminal corymbs. 

 Found in sandy fields. Root large, fleshy, sending up numerous steins. 

 These are about 2 feet high, leafy, erect or ascending, hairy and colored. 

 Leaves hairy, scattered, only the upper ones quite sessile, lanceolate, acute 

 or acuminate, obtuse at base, 2 — 4 inches long, ^ — 1 inch wide. The corymb 

 consists of numerous bright orange-colored flowers. Petals 5, oblong, reflexed, 

 concealing the small calyx. Pods or follicles lanceolate, pointed, and, like 

 the other species, containing long, silky down uniting the flat, ovate seeds to the 

 receptacle. Aug. Per. Medicinal. Tuhtrous-rooted Asclepias, Bulterfly-weed. 



