The CO2 capacity of the serum is markedly lowered early in infection with Trypanosoma equiperdum. The non-protein nitrogen and uric acid constituents of the blood are increased in the terminal stages. The kidneys also show terminal degenerative changes. The cholesterol remains unchanged throughout. Lecithin is markedly increased, most of the observations showing a 20 per cent to 50 per cent rise in this substance. Liver glycogen is lower than normal in the early stages and could not be demonstrated in the later stages of the infection. The blood sugar remains normal until a very late period in the disease.