Photoemission spectra of Bi2Sr2CaCu2O8 + δ below Tc show two features near the (π, 0) point of the zone: a sharp peak at low energy and a higher binding energy hump. We find that the sharp peak persists at low energy even as one moves towards (0, 0), while the broad hump shows significant dispersion which correlates well with the normal state dispersion. We argue that these features are naturally explained by the interaction of electrons with a sharp mode which appears only below Tc, and speculate that the latter may be related to the resonance seen in recent neutron data. © 1997 American Physical Society.