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. — Pioc. Am. Acad. xii. 66. Ananlherix in part, 



Nutt. 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 r leaves 



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



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



the lobes a third to half inch long : hoods purphsh 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. — ^sc/eT^icw viridis, Walt. Car. 107. Podostipna? viridis, Ell. Sk. i. 327. 



Anantherix panicidatus, Nutt. Trans. Am. Phil. Soc. 1. c. A. Torreyanus, Don, Syst. iv. 146. 



Asclepias longipetala, 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 AUe- 



ghanies north to Illinois. 



Var. angustior, 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. deciimbens, Gray, I. c. Scabrous-puberulent : leaves firmer m texture, from lan- 

 ceolate to linear, tapermg to the, apex: umbel sohtary : corolla depressed-globular in bud 

 4 or 5 hues 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: polhuia pyriform, short-caudicled. — ^mn- 

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

 talhanus, 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. FoUicles always' 

 smooth? (Adjacent Mex.) 



6. ASCLlfiPIAS, L. Milkweed, Silkweed. (The Greek name of 

 ^sculapius, 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. (Butteefly-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. 



