  We identify two Cabibbo suppressed $D^+$ decay modes with anomalously high
branching ratios which are not simply explained by any model. All standard
model diagrams that can contribute to these decays are related by symmetries to
diagrams for other decays that do not show any such enhancement. If these high
branching ratios are confirmed by more precise experiments, they may require
new physics to explain them. Anomalies in $D_s$ decays and tests for possible
violation of G-parity are discussed.
