362 ASCLEPIADACEJE. (MILKWEED FAMILY.) 



1. ASCLEPIAS, L. MILKWEED. SILKWEED. 



Calyx 5-parted. Corolla wheel-shaped, deeply 5-parted, reflexed. Crown 

 composed of 5 hooded leaves, each containing an incurved horn-like appendage. 

 Pollen-masses 10, by pairs, each pair occupying the contiguous cells of adjacent 

 anthers, and suspended by a slender stalk from the projecting angles of the stigma. 

 Follicle many-seeded. Seeds obovate, flat, usually comose. Perennial herbs, 

 with mostly simple (not twining) stems, and opposite alternate or whorled leaves. 

 Flowers in lateral (between the leaves) and terminal umbels. 



1. Stems herbaceous : seeds comose. 

 * Follicles spiny : leaves opposite. 



1. A. Cornuti, Decaisne. Softly pubescent ; stem stout, erect, obscurely 

 4-angled ; leaves oval-oblong, short-petioled, mucronate, soon smooth above, the 

 lowest somewhat cordate ; umbels numerous, many-flowered, long-peduncled ; 

 corolla greenish-purple, one fourth as long as the pedicels ; leaves of the crown 

 pale purple, ovate, obtuse, longer than the incurved horn ; follicle ovate-oblong, 

 woolly, armed with soft spines. (A. Syriaca, L.) Fields and road-sides, New 

 Berne, North Carolina, Groom, and northward. June and July. Stem 3 - 4 

 high, sometimes branched. Leaves 4' - 8' long. Pedicels 1' - \^( long, purplish. 

 Corolla ' wide. 



=fc * Follicles spineless. 

 *- Leaves opposite, oval or oblong, narrowed into a petiole. 



2. A. phytolaccoides, Pursh. Stem tall, smooth; leaves ovate or 

 ovate-lanceolate, tapering at each end, paler and minutely pubescent beneath, 

 membranaceous ; umbels long-peduncled, many-flowered; pedicels filiform, 

 drooping, nearly as long as the peduncle ; corolla pale greenish ; leaves of the 

 crown white, truncated, 2-toothed, shorter than the subulate incurved horn. 

 Low grounds along the mountains, and northward. June and July. Stem 3 - 

 5 high. Leaves 6' - 9' long. Pedicels 2' - 3' long. 



3. A. purpurascens, L. Stem smooth ; leaves ovate-oblong, acute, 

 short-petioled, paler and pubescent beneath ; umbels 1-2, terminal, peduncled, 

 many-flowered ; pedicels half as long as the peduncle, and twice as long as the 

 dark purple corolla ; leaves of the crown oblong, abruptly contracted above, 

 twice as long as the incurved horn and nearly sessile gynostegium. Thickets 

 and borders of woods, Tennessee, North Carolina, and northward. June and 

 July. Stem 2 -3 high. Leaves 4' -7' long. Pedicels 9" -15" long, pu- 

 bescent. 



4. A. variegata, L. Stem stout, leafless below, pubescent in lines ; leaves 

 oval, oblong, or obovate, cuspidate, smooth on both sides ; umbels 3-5, pubes- 

 cent, closely flowered, the upper ones corymbose ; pedicels erect, as long as the 

 peduncle ; corolla white ; leaves of the crown roundish, longer than the purplish 

 gynostegium, equalling the thick awl-pointed incurved horn. (A. nivea, Pursh.) 

 Dry open woods and borders of fields, Florida 1 to Mississippi, and northward. 

 May and June. Stem 2 - 3 high, purplish. Leaves rather thick, 2' - 3' long. 

 Peduncles 9" - 12" long. 



