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XI] number, show a relatively increased percentage as in some other protozoal diseases. He further states that the alkalinity of the blood is diminished.

In those cases which I have had an opportunity of carefully watching I have been struck with the fact that, notwithstanding the chronic fever and progressive wasting, throughout the long illness the tongue has been almost uniformly clean and the appetite and digestion good.

Morbid anatomy.—— The spleen is greatly enlarged and the thickened capsule may show signs of perisplemtis. The trabeculse are enlarged, the pulp increased in bulk and full of blood. A section or smear preparation, appropriately stained, will show prodigious profusion of parasitic growth in the crowds of the large mononuclear cells already referred to. The liver also is generally much enlarged. It has a brown or mottled section. The parasites are in great abundance, occupying large mononuclear cells, attached or free, in the dilated hepatic and portal capillaries. There may be some cirrhotic changes, but the hepatic cells, though atrophied and perhaps fatty, never contain parasites. The bone marrow is similarly packed with parasite -lad en cells. Intestinal ulcerations is very common, and parasites may be found in the walls of the ulcers as well as in skin lacerations or in the lymphatic glands. Occasionally they are found in connection with the blood-vessels in the kidneys, but never in the epithelium of the secreting tubules. Diagnosis.—— Irregular chronic fever with enlargement of the spleen and a relative mononuclear leucocytosis in patients from the endemic zone suggests kala-azar. An examination of the blood can at once exclude leucocythæmia and, if taken together with absence of tertian or quartan periodicity and the inefficacy of quinine, malaria. Trypanosomiasis and kala-azar may be difficult to distinguish between, and unless their respective parasites are detected a positive diagnosis is impossible, although geographical considerations and subsidiary skin and lymphatic lesions may assist in forming an opinion,