ASCLEPIADE^E. 237 



** Leaves opposite. Nectary without horns. ACERATES. 



13. A. viridiflora Raf. : stem erect, simple, hairy ; leaves oblong, on 

 short petioles ; tomentose-pubescent on both sides, obtuse ; umbels la- 

 teral, solitary, subsessile, nodding, dense ; pedicels tomentose ; horns 

 of the nectary wanting. A. nutans Muhl. 



b. obovata Torr. : leaves obovate. A. obovata Ett. 



HAB. Sandy fields. N. S. W. to Miss. July. 2J..Stem 2 feet 

 high, very pubescent. Leaves thick, nearly sessile, varying in 

 in form. Umbels about 3, on long peduncles. Flowers green. 



14. A. lanceolata Ives : stem decumbent, hirsute ; leaves opposite, 

 lanceolate, acute, subsessile, hirsute ; umbels lateral, solitary, sessile, 

 nodding, subglobose, dense flowered ; horn of the nectary wanting. 

 A. viridiflora var. lanceolata Torr. 



HAB. Near New Haven, Conn. Ives. July. If. Certainly dis- 

 tinct from the preceding. 



*** Leaves alternate. 



15. A. tuberosa Linn. : stem erect, hairy, with spreading branches ; 

 leaves oblong-lanceolate, sessile, alternate, somewhat crowded} um- 

 bels numerous, forming terminal corymbs. 



HAB. Sandy fields. Can. to Car. W. to Miss* July, Aug. 

 14.. Root large, tuberous. Stem 2 3 feet high, with spreading 

 branches above. Flowers large, in numerous erect umbels, 

 bright orange. Medicinal. Big. Med. Bot. ii. 59. 



Pleurisy Root. 



2. GONOLOBUS. Mich. 



Corol rotate, 5-parted. Stamineal crown scutelliform, 

 lobed. Anthers opening transversely, terminated by a mem- 

 brane. Pollinia 5 pairs, not separating into grains. Stigma 

 flattish-depressed. Follicles 2, ventricose. Seeds comose. 



Pentandria. Digynia. 



1. G. obliquus Brown: stem climbing, hairy; leaves ovate-cordate, 

 villous, acute ; corymbs axillary ; segments of the corol ovate, acumi- 

 nate, oblique, revolute; calyx small. Cynanchum obliquum Muhl. 



HAB. Near Philadelphia, Penn. Bart. July. If.. Stem 45 

 feet long. Leaves veined on both sides. Umbels axillary, much 

 shorter than the leaves. Flowers fetid, dark purple. 



2. G. hirsutus Mich. : stem twining ; younger branches very hairy ; 

 leaves cordate-oval, acuminate, pubescent on both sides ; segments of 

 the corol linear-oblong ; follicles oblong, muricate. Gonolobium hir- 

 sutum Pursh. 



HAB. Hedges near streams. Penn. to Car. Pursh. June, July. 

 If. Stem trailing and climbing, 3 4 feet long, pubescent. 

 Leaves slightly auriculate at base. Umbels axillary, 3 4-flow- 

 ered. Flowers dark purple. 



