The Nomenclature of Plasmodium Ovale Stephens 1922

In the Report of the Surgeon General of the United States Army, for 1900, the writer (1) described a malaria plasmodium occurring in the blood of soldiers returning from the Philippine Islands and suffering from a fever presenting tertian paroxysms indistinguishable clinically from the paroxysms of fever caused by Plasmodium vivax, the tertian malaria plasmodium. The differences in morphology between this plasmodium and Plasmodium vivax led the writer to regard it either as a distinct variety of the latter plasmodium or as a strain of Plasmodium vivax that had acquired the peculiar morphological characteristics described through some unknown environmental condition. The writer did not give this plasmodium a name because of the uncertainty as to its exact zoological position and because it was believed that further observations would decide whether or not it was entitled to be regarded as a new variety or species of malaria plasmodium.