Abstract

Either spontaneous or transplanted mammary tumors, inoculated subcutaneously into homologous hosts, have shown differences in transplantability and lethality, depending upon the size of the tumor at the time of its transplantation. * Assisted by grants from the Minnesota Division of the American Cancer Society and the U.S. Public Health Service. Present address: Department of Biochemistry, University of North Dakota, Grand Forks, N.D.