During the past year an opportunity became available for the study of four rhesus monkeys that were carriers of Endamoeba histolytica. The presence or absence of lesions in human carriers of dysentery amoebae has an important bearing on the relations between the amoebae and their hosts during the carrier period and on the treatment of the hosts. Amoebic infections in monkeys appear to be very similar to those in human beings hence the results of their study should throw considerable light on host-parasite relations in human amoebiasis.
Four female rhesus monkeys were used in these experiments; their ages were not known, but two were much younger than the other two, hence two distinctly different ages were represented. These monkeys were kept in this laboratory for one and one-half years.