A movement of this type whose theme is stated forwards and backward at the same time was penned by Josquin des Prez (joe-SCAN deh-PRAY), who may have tried to one-up Johannes Ockeghem (oh-kuh-GHEM) with another of these movements featuring a three-voice mensuration canon. A seventh voice is called for in the second of these movements in the otherwise six-voice (-5[1])Pope Marcellus Mass. This portion of the mass, which Renaissance composers often divided into three parts, contains the ■END■