Earthworms are capable of destroying antigenic tissues. Autogeneis transplants healed in regularly and remained permanently viable. Xenografts, by contrast were cicatrized but eventually rejected. Intrafamilial transplants survived longer than interfamilial ones. Xenografts and autografts placed in the graft bed were joined to each other but xenografts were later destroyed although autografts were not. Two xenografts from Eisenia to Lumbricus, performed simul taneously, showed survival endpoints similar to a single xenograft. A 5-day interval between first- and second-set grafting led to an accelerated rejection of both transplants. First-set Allolobophora transplants to Lumbricus performed simulataneously with second-set Eisenia grafts were destroyed at a time different from either of the two Eisenia transplants. A single Allolobophora transplant to Lumbricus was rejected at survival tines equivalent to Allolobophora along with two Eisenia transplants.