A method of anaphylaxis with desensitization was used to show on guinea pigs the presence of sex-linked antigens in the kidney and liver tissues of male mice (C57BL inbred strain). In the majority of the guinea pigs there occurred anaphylactic shock symptoms in response to the injection of the antigen of male mice. Tissues of female mice caused no distinct anaphylactic shock symptoms in guinea pigs in the same experimental conditions. Since a number of guinea pigs exhibited a weak anaphylactic reaction evidently female tissues also contained antigens specific to the female organism, but in low quantities.