Herb, to ca 1 m tall, woody at base in age; cut parts with a foul aroma; inconspicuously appressed-pubescent on stems, axes of inflorescences, and leaves, especially on veins. Petioles 5-20 cm long; blades narrowly elliptic to obovate, acuminate or acute at apex, acute at base, 5-16 cm long, 2-6 cm wide. Flowers white, in sparsely flowered, terminal or upper-axillary racemes 15-40 cm long; pedicels ca 1 mm long; tepals 4, white or greenish-white (sometimes pinkish), spreading, united at base, 3-5 mm long, erect, green and persistent in fruit; stamens 8, fully exposed at anthesis, to ca 3 mm long; filaments unequal; anthers linear, dorsifixed; ovary densely pubescent, bearing 4 uncinate green appendages at apex, the hooks becoming enlarged and prominent in fruit (probably aiding in epizoochorous dispersal); stigma finely dissected, subapical. Achenes linear, bilobed at apex, to 8 mm long, each lobe bearing hooks to 4 mm long. Croat 17051. Uncommon, in the forest beyond the Tower Clearing. Flowers and fruits throughout the year, principally in the rainy season. Southern United States to Argentina; West Indies. In Panama, known from tropical moist forest in the Canal Zone, Bocas del Toro, Chiriqui, Panama, and Darien, from tropical dry forest in Los Santos, Herrera, and Panama, from premontane moist forest in the Canal Zone, and from premontane wet forest in Chiriqui and Coclé