any of about 42 species of tropical American orchid (family Orchidaceae) that has an unusual pollination mechanism. One to five flowers are borne on a pendent stem that arises from the base of the tall pseudobulbs (bulblike stems). A fluid secreted by specialized glands collects in the column, which has a spoutlike opening just below the pollen packets. An insect attracted by the strong odour produced by the upper fleshy part of the lip slips into the bucket. As the only way out is through the spout, the pollen packets stick to the insect as it crawls out of the bucket and are deposited on the stigma of the next bucket orchid that the insect enters.