Asclepias. ASCLEPIADACE^. 89 



therix by the same characters. Leaves mainly alternate or scattered. Flowers 

 proportionally large : corolla-lobes ovate, greenish. Follicles ovate or oblong and 

 acuminate, usually bearing some scattered soft-spinulose projections, arrect on 

 recurved or sigmoid pedicels. — Proc. Am. Acad. xii. 66. Anantherix in part, 

 Xutt. in Trans. Am. Phil. Soc. 1. c. Acerates in part, Decaisne, 1. c. 



A. viridis, Gray, 1. c. About a foot high, almost glabrous, very leafy to the top : leaves 

 from ovate-oblong to oblong-lanceolate, mostly obtuse, short-petioled, 3 or 4 inches long: 

 umbels few and corymbose or clustered, sometimes solitary : corolla globular-ovate in bud; 

 the lobes a third to half inch long : hoods purplish or violet, about half the length of the 

 corolla-lobes, lower than the anther-column : wings of the anthers narrow, hardly angulate 

 above, and below less prominent than the connectives : pollinia narrow, little longer than 

 their caudicles. — Asclepias viridis, Walt. Car. 107. Podostigma ? viridis, Ell. Sk. i. 327. 

 Anantherix pam'culatus, Xutt. Trans. Am. Phil. Soc. 1. c. A. Torreyanus, Don, Syst. iv. 146. 

 Asclepias lonaipetala, Scheele in Linn. xxi. 757. Acerates paniculata, Decaisne, 1. c. 521. — 

 Prairies and dry barrens, S. Carolina to Texas, New Mexico, and westward of the Alle- 

 ghanies north to Illinois. 



Var. angrtistior, a lower form, with smaller and oblong-linear leaves, and rather more 

 assurgent hoods. — Anantherix paniculatus, var. angustior, Engelm. ined. — Texas, Lindheimer, 

 E. Hall. 



A. decumbens, Gray, 1. u. Scabrous-puberulent : leaves firmer in texture, from lan- 

 ceolate to linear, tapering to the apex : umbel solitary : corolla depressed-globular in bud, 

 i or 5 lines long, hardly twice the length of the yellowish or dark-purplish hoods, which 

 overtop the somewhat depressed anther-column : anther-wings salient, especially at the 

 broader and strongly angulate upper portion: pollinia pyriform, short-caudicled. — Anan- 

 therix decumbens, Xutt. 1. c. (& in Torr. Ann. Lye. N. Y. ii. 219, without name). — A. Nut- 

 tallianus, Don, Syst. iv. 147. Acerates decumbens, Decaisne, 1. c. Asclepias brevicornu, Scheele, 

 1. c. 756. — Dry plains, Arkansas and Texas to New Mexico and Utah. Follicles always 

 smooth 1 (Adjacent Mex.) 



6. ASCLEPIAS, L. Milkweed, Silkweed. ('Ao-/cA»/?rids, latinized 

 jffisculapius, applied by the ancient herbalists to various plants of the present and 

 the preceding order.) — Herbs, rarely woody at base (American, mainly North 

 American with one or two African) : upright or merely spreading stems from 

 deep and thickish perennial roots : leaves opposite varying to verticillate, or 

 sometimes alternate or irregularly scattered. Flowers (in summer) umbellate ; 

 the peduncles terminal and lateral, usually between the petioles. Stem often 

 marked with decurrent lines of pubescence. Follicles soft-echinate or warty in 

 two or three species, otherwise naked. Coma of the seeds often wanting in A. 

 perennis. Corolla not reflexed in A. Feayi. — Benth. & Hook. Gen. ii. 754 ; Gray, 

 Proc. Am. Acad. xii. 66. 



§ 1. Hoods sessile, broader or at least not attenuate at base ; the horn or crest 

 various, but conspicuous : anther-wings broadest and usually angulate-truncate 

 and salient at base. 

 # Corolla and hoods, orange-color : follicles arrect on a deflexed fruiting pedicel, naked : leaves 

 mostly irregularly alternate, seldom truly opposite : juice of stem not milky ! ■ 

 .A. tuberosa, L. (Butterfly-weed, Pleurisy-root.) Hirsute or roughish-pubescent, a 

 foot or two high, very leafy to the top : leaves from lanceolate-oblong to linear-lanceo- 

 late, sessile or slightly petioled : umbels several and mostly cymose at the summit of the 

 stem, short-peduncled : column short: hoods narrowly oblong, erect (2 or 3 lines long), 

 deep bright orange, much surpassing the anthers, almost as long as the purplish- or 

 slightly greenish-orange oblong corolla-lobes, nearly equalled by the filiform-subulate 

 horn: follicles cinereous-pubescent. — (Dill. Elth. t. 30, f. 34.) Bot. Reg. t. 76 ; Bart. Med. 

 t. 22; Bigel. Med. t. 26. Dry and especially sandy soil, Canada to Florida, Texas, 

 and Arizona. 



