When typhoid and malarial fevers prevail coincidently, particularly when atypical forms of each occur, the diagnosis in a given case may be attended with the greatest difficulty and a correct decision may be possible only after invoking the aid of all refinements in physical exploration. A positive reaction with the serum agglutinating test on the one hand and the presence of the plasmodia in the blood on the other hand, together with other more or less characteristic symptoms, may leave no room for doubt, but occasionally these phenomena may for one reason or another be absent. It seems not impossible that the different infectious diseases are attended with more or less definite, perhaps specific, changes in the blood and the near future may yield additional diagnostic means of great precision and certainty.
We have already referred to the agglutinating test and the hematozoön of malaria. It is further known that