330 MATZUSIRO TAKENOUCHI 



Histological examination does not reveal any difference in the 

 structure of the thymus or testes of the test and control rats. 

 The spermatogenesis in the injected rats does not indicate any 

 specific action of the injected antitestis serum. 



5. IMMUNIZATION OF THE RABBIT WITH THE RED CORPUSCLES 

 OF THE ALBINO RAT (RABBIT, GROUP C) 



Since the experiments on the action in vitro, as well as in 

 vivo, of the antithymus and antitestis sera showed almost 

 entirely negative results, and since it became evident that the 

 production of antibodies in the rabbit against the tissues of the 

 albino rat is very faint, I tried to immunize a rabbit against the 

 blood-cells of the albino rat, because the hemolytic test is rather 

 easier than any other in vitro and the reaction of normal rat 

 complement could be determined more definitely in this way. 



a. Process of immunization 



Although, as already noted in the immunization of rabbits 

 with the different organs of the rat, the hemolysin production in 

 the rabbit by the injection of rat organs, or even by the injec- 

 tion of rat erythrocytes, is very faint, nevertheless I tried once 

 more to make sure of this matter. 



A large adult female rabbit (rabbit, group C, no. 1) was 

 given an injection of rat corpuscles (0.5 cc. of 10 per cent sus- 

 pension in physiological salt solution) on October 31, 1918, 

 intraperitoneally. The rabbit did not show any abnormal sign 

 immediately caused by the injection. On November 8, 1918, a 

 double dose, 1 cc. of 10 per cent suspension of rat corpuscles 

 was injected intraperitoneally. After one and a half hours the 

 rabbit became very weak and died shortly in convulsions. The 

 autopsy did not show the immediate cause of death. The blood 

 was removed, however, directly from the heart and vena cava 

 inferior at the upper region of the liver, and the clear serum 

 separated. 



This serum was tested for its hemolytic power against rat 

 corpuscles with an entirely negative result. Hemolytic action 



