Continuing their investigation of the presence or absence of an immunological memory in adult Amphibian Urodeles, and in Triturus cristatus in particular, the Authors performed the following transplants: 1) on a normal host, two simultaneous skin allotransplants from two normal donors (Batch I); 2) on a host inoculated with a suspension of spleen cells 10 days earlier, two simultaneous skin allotransplants from two donors, from one of which the spleen suspension had been taken (Batch II A, Batch II B). The histological appearance of the transplants and above all the extent of lymphocyte infiltration observed in them (after 20 and 40 days presence in the host), and the fact that no significant differences were found between the degenerative pattern of the skin transplants from the individual providing the spleen cell suspension (Batch II A) and that of the skin transplants in which the spleen cell suspension and the actual skin came from two different individuals (Batch II B), together with the fact that no important differences were noted even between these results and those obtained in the Batch I skin transplants, run as controls and in which no host stimulation had been performed prior to grafting, are taken by the Authors as further evidence of the postulated absence in Triturus cristatus of immunological memory of the type found in the higher Vertebrates.