This is the bud of a corpse flower, Amorphophallus titanum. At the time that the photo was taken, the blossom was 5 ft and 7 in (5.6 m), and expected to reach over 6 ft (3 m). When open the corpse plant smells of rotting meat, to attract their fly and bee pollinators. The flower has a purplish color (like rotting meat) and heats up the air around it, so that the scent diffuses farther.
These plant produce only one flower or one leaf at a time. The flower itself is not a single large flower, but is made up of smaller male and female flowers. The leaf can reach 20 ft (6 m) tall and 16 ft (5 m) across. They are closely related to calla lilies.