LLCA of cats were produced by using inactive cow serum and LLCA of rabbits were by alpha-streptococcns. The motor cortex and nucleus lenticularis were investigated microscopically. The capillary vessels were studied with Campbell-Wake's capillary vessels representation method and gutta percha injection into the common carotid artery. The capillary vessels of LLCA were fragmentally broken by Campbell-Wake's method for 1 or 2 months after the last injection of antigen, but 3 months later no difference was observed between LLCA and the normal ones. Therefore, it was presumed that the capillary vessels of the brain with LLCA were spastic, at least for 1 month after the last injection.