Studies of Inheritance in Guinea-Pigs and Rats #255549

For several years I have been engaged in studies of heredity in guinea-pigs. In the course of these studies all the common varieties of guinea-pigs have been investigated by the method Of experimental breeding and something has been learned concerning their inter relationships and probable mode of origin. The actual origin of most of these varieties is, however, unknown, as is true also concerning most varieties Of domesticated animals. One or two varieties have.