Studies on the Morphology of the E. histolytica-like Amoebae Found in Monkeys

With the advent of the present century, protozoologists began to evidence interest in the protozoa to be found in primates other than man. In the steady accumulation of literature, the amoebic organisms found in monkeys have received much attention, mainly because of their apparently close relationship to the endamoebae in human hosts. Much has already been published in attempts to demonstrate the similarity or dissimilarity between the intestinal endamoebae in man and those in monkeys, which two hosts are, in themselves, of close evolutionary relationship. Investigators who first encountered amoebae in monkeys often erected new species names without adequate distinction from those already known in man. Since then, however, there has evolved the increasingly accepted belief that the endamoebae of man and monkey are identical, and recent literature divides the endamoebae of monkeys into those similar, or identical, to Endamoeba coli in man, and those similar, or identical, to Endamoeba 'histolytica in man. This paper will attempt to establish that the amoebae of monkeys, with specific reference to the E. histolytica-like type, are not all identical with those in man. The writer has employed both qualitative and quantitative tests of more precise nature than heretofore employed, which, it is believed, will reveal more clearly the morphological differences among the E. histolytica-like amoebae parasitic in monkeys.