1. Department of Earth and Atmospheric Sciences, Indiana University Bloomington, Bloomington, Indiana 47408 U.S.A.,
2. Department of Biology, High Point University, High Point, North Carolina 27268 U.S.A.,
3. Forschungsinstitut Senckenberg, Abt. Messelforschung und Mammalogie, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany,