PENTANDRIA, DIGYNIA. 
131 
(angular, without alated lateral margins or 
terminal membranaceous cusps. PolUnia 
(masses of pollen) 5 pair, even, transverse. 
Follicles Seed comose. — J\Tutt. 
1. G. stem twining, hirsute ; leaves ovate-cordate, oWiquus. 
acute 5 corymbs axillary j segments of the Co- 
rolla ovate acuminate. 
Gonolobus obliquus, Muhl. 
Cynanchum obliquum, L. Sp. pi. 1. p. 1256. 
A twining- plant with dark purple flowers, with linear 
spreading petals. On the banks of the Schuylkill from Lemon- 
hill to the falls. On the botanic garden-ground of the Uni- 
versity of Pennsylvania. Not common. Perennial. June. 
124. ASCLEPIAS. Gen. pi. 429. fJpocynea.J 
Calix small, 5 parted, persistent. Corolla 
rotate, mostly reflected. Lepanthium (nec- 
tary, L. ) simple, 5-parted, segments ovate, 
cucullate, each producing from its base an 
internal subulate averted awn. Antheri- 
dium 5-parted, crustaceous, sessile, angles 
opening by 5 longitudinal chinks. Follicles 
2, ventricose, acuminate, smooth or muri- 
cate. Seed comose. — JSTutt. 
1. A. stems simple, leaves lanceolate-oblong, syriaca. 
acute tomentose beneath ; umbels somewhat iiu- 
tant, tomentose. — Willd. and Purslu 
A. Syriaca /3. Mich. 
A. Illinoensis, /3 Syriacse, Pers. 
Milk-weed. Syrian Swallow-wort. Silk-weed. 
Wild-cotton. 
The commonest species of this genus in this neighbourhood. 
From three to four feet high. On the banks of the Schuyl- 
kill, Delaware, and all our creeks, very frequent. Perennial. 
June. 
£. A. stem erect, simple, leaves broad-ovate- oblong, phytoiacc©i= 
acute, smooth, paler underneath j umbels com- 
