A modified passive cutaneous anaphylactic test requiring intracutaneous sensitization and intracutaneous antigen challenge in the same site was evaluated. Challenges with concentrations of Trichinella antigen in excess of 12 µg caused nonspecific reactions. The location of the sensitized site on the guinea pig's back did not significantly influence lesion size. The size of the lesion varied directly with the antibody concentration used for sensitization and the amount of challenge antigen. The test procedure detected antibody in Trichinella-infected rabbits by the 3rd week of infection.