  The resistivity and the thermopower for Bi2Sr2Ca{1-x}RxCu2O8 single crystals
are measured and analyzed with a special interest in the parent antiferromagnet
insulators. Above room temperature, the parent insulators show an electric
conduction confined in the CuO2 plane and a decreasing thermopower with
temperature, which are very similar to those for high-$T_c$ cuprates. These
data strongly suggest that essential anomalies of high-Tc cuprates inheres in
the parent insulators.
