Polyacrylamide gel electrophoresis of saliva infected with Trypanosoma brucei showed few, very faint protein bands as compared to 11 bands from clean saliva. If the saliva collected is 6 times the normal amount, infected saliva showed all 11 bands, plus one more. Inositol and galactosamine did not appear in infected saliva. Infected saliva contained sphingomyelin in addition to phosphatidylethano-lamine, phosphatidylinositol and phosphatidyllecithin.