46 Population Genetics of T/t Complex Mutations
Dorothea Bennett

47 Individual Mice of One Inbred Strain Produce Anti-H-2 Antibodies of Different Specificites
Pavol Ivanyi and Paul de Greeve

48 Studies on Histocompatibility Antigens and Hybrid Sterility Gene in Wild Mice: A Short Survey
Pavol Ivanyi

49 Characterization of H-2 Haplotypes in Wild Mice
Jan Klein, William R. Duncan, Edward K. Wakeland, Zofia Zaleska-Rutczynska, Huei-Jen S. Huang, and Ellen Hsu

50 Four Major Endogenous Retrovirus Classes each Genetically Transmitted in Various Species of Mus
Robert Callahan and George J. Todaro