1. Hemolymph from the giant African snail Archachatina marginata has been analyzed for its content of certain lysosomal hydrolases and shown to contain substantial quantities of acid phosphatase (285 units/ml) hexosaminidase (512 units per ml) and beta-glucuronidase (28 units/ml). 2. Hemolymph acid phosphatase can be fractionated into 6 active components by DEAE-Sephadex chromatography. 3. Some of the acid phosphatase species can be distinguished on the basis of heat stability, pH dependency and sensitivity to inhibitors including phosphate, L(+) tartrate, fluoride, formaldehyde and 1.10 phenanthroline.