Amorphophallus titanum (from Ancient Greek amorphos, "without form, misshapen" + phallos, "phallus", and titan, "giant"), known as the titan arum, is a flowering plant with the largest unbranched inflorescence in the world. The titan arum's inflorescence is not as large as that of the talipot palm, Corypha umbraculifera, but the inflorescence of the talipot palm is branched rather than unbranched.
Due to its odor, which is reminiscent of the smell of a decomposing mammal, the titan arum is characterized as a carrion flower, and is also known as the corpse flower, or corpse plant (Indonesian: bunga bangkai – bunga means flower, while bangkai can be translated as corpse, cadaver, or carrion). For the same reason, the title corpse flower is also attributed to the genus Rafflesia which, like the titan arum, grows in the rainforests of Sumatra.
Further info: http://en.wikipedia.org/wiki/Amorphophallus_titanum