Plant: Perennial herbaceous vine; Stems pubescent in lines above the petioles; milky sap Leaves: ovate-cordate, 2-13 cm long, less than 2 times longer than broad, glabrate above, sparsely pubescent on the veins beneath; petioles pubescent above, shorter than to about as long as the blades INFLORESCENCE: racemose, tardily elongating to ca. 6 cm, the peduncles mostly 1-3 cm long Flowers: 9-11 mm long; calyx lobes 3-5 mm long; corolla white (in ours), broadly open-campanulate, the tube 2-3 mm long, the lobes oblong, spreading-recurved, 6-9 mm long, sparsely pubescent inside; crown whitish, 8-9 mm long, the segments 6-8 mm long, erect and conspicuous, ovate with attenuate-ligulate tips exserted ca. 4-5 mm beyond the stigma-head, united at their base into a ring 1-2 mm high; anther wings ca. 1 mm long; corpusculum ca. 0.3 mm long, the pollinia ovoid-ellipsoid, ca. 0.4 mm long; stigma head apically rounded Fruit: FOLLICLES 8-9 cm long Misc: Aug REFERENCES: Sundell, Eric. 1994. Asclepiadaceae. J. Ariz. - Nev. Acad. Sci. Volume 27, 169-187.