typhoid, which closely simulates it, as well as malaria. Basset Smith states that if the clumping power is low and the symptoms are severe the prognosis is bad, whilst if high and sustained it is good. It is only right to mention that although probably diagnostic in the hands of Wright and certain others, yet, in the hands of many, this serum reaction has proved unsatisfactory, probably through faulty technique. At the London School of Tropical Medicine it has proved of value in settling the diagnosis in some obscure cases. In Malta fever also there is no leucocytosis, but a relative lymphocytosis.
Cerebro-spinal meningitis may simulate malaria, but here there is usually a marked leucocytosis. In tuberculosis the lymphocytes show a relative increase.
Kala-azar has more often than not been diagnosed as malaria or malarial cachexia; it has also been labelled as a leuchæmia or splenic anæmia. By blood examination we find no malaria parasites or pigment, unless there be a concurrent attack, and there is no leucocytosis but usually a marked leucopenia—3700 and 1900 being the counts in two cases at the London Tropical School. There is a lymphocytosis with relative increase of the large mononuclears. Very rarely indeed have Leishman-
