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Numerous Raman investigations of the 90-K phase of ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$ have revealed broad features at approximately 350 and 500 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ in the ${\mathit{A}}_{1\mathit{g}}$ and ${\mathit{B}}_{1\mathit{g}}$ symmetries, respectively, which exhibit behavior qualitatively similar to the ``gap'' redistribution expected of a BCS-like superconductor. We find, however, that in decreasing the oxygen concentration to achieve an untwinned ${\mathit{T}}_{\mathit{c}}$=60 K single crystal the gaplike features do not exhibit straightforward BCS behavior. Rather, the 500-${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ ${\mathit{B}}_{1\mathit{g}}$ peak is found to be insen- sitive to the change in carrier concentration and is found to persist well into the normal state while the ${\mathit{A}}_{1\mathit{g}}$ peak exhibits significant broadening and no apparent softening. In addition, we present results on the room-temperature phonons and on an anomalous response of the background continuum to incident laser power.

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