In talking to Bernard, he told me that he was under the impression that "Mephistopheles" was a Wayne Shorter tune, so he asked to use a track from another session that Brown recorded. This was "Exhibition." The problem was resolved later and they used the master for the November 1965 session for subsequent material, but neglected to change the title. The masters for both sessions are safe, and ESP will be reissuing all of it later this summer, apparently with both "Mephistopheles" and "Exhibition."
Cheers,
CT