With an arrangement more suited to a woozy Salvation Army band than a rock group, the giddily psychedelic non sequiturs of "Mellow Yellow" wormed their way just shy of the Numner One spot. Backup vocals were contributed by Paul McCartney, who had used a phrase by Donovan in "Yellow Submarine." The "electrical banana" in "Mellow Yellow" was a vibrator, but it fueled rumors that you could get high by smoking the peel of that fruit. Country Joe McDonald revealed himself to Donovan as the source of that urban legend many years later, telling the singer, "By the way, man — the 'mellow yellow' s—? The bananas? It was me."