The cats with latent local cerebral anaphylaxis were produced by injecting inactive bovine serum antigen. During 300 days after the last effective injection, anaphylactic antibody in the blood and electrophoretic fraction of serum protein were investigated by precipitin reaction and the use of Tiselius apparatus. 1) The title of antibody stays at maximum meanly during 60 days after the last effective injection and then gradually decreases. After 120 days it descends markedly. But even after a considerable period of time as 300 bays it still can be proved. 2) The ups and downs of total protein and globulin shows a parallel relation with that of γ-globulin. Their increase is regarded to owe to that of γ-globulin. No difinite relation is seen between the ups and downs of protein, α-globulin and γ-globulin. 3) The ups and downs of the title of antibody and that of γ-globulin were compared. The latter shows a tendency of an earlier descending than the former but generally they have a parallel relation. In the latent local cerebral anaphylactic cats the abnormal irritability of brain nerve cells especially the descending threshold of cardiazol seizure has been proved by many works done in our institute. In such cats the title of antibody is high, can be kept during a long time and also the increase of γ-globulin is seen. This fact can be proof that cats with LLCA is disposed to convulsion by any stimulation.