AbstractOne membrane‐bound α‐glucosidase and two soluble α‐glucosidases were isolated from homogenates of the hind‐midgut, the main digestive region inMusca domesticalarvae. The membrane‐bound α‐glucosidase and the low‐Mr soluble α‐glucosidase hydrolyze maltopentaose better than maltose, maltotriose, and maltotetraose, the reverse being true for the high‐Mr soluble α‐glucosidase. A membrane‐bound glucoamylase previously described inMusca domesticamidgut was shown by gradient centrifugation and dialysis against EDTA to result from the combined action of an amylase and an α‐glucosidase. The determination of amylase, α‐glucosidases, soluble and membrane‐bound carboxypeptidase A, membrane‐bound aminopeptidase and dipeptidase along the tissue and luminal contents of the hind‐midgut is described. The data support a proposal concerned with how starch and protein are digested inMusca domesticalarval hind‐midguts and where and how midgut