I cant seem to find the file anymore, but I was researching the Duvernoy's gland for a school project, and found some other possible uses for it. In species like ordinoides that feed primarily on invbertebrates, the secretions contain traces phospholipase A, and it is thought to be used to increase the surface area of prey for digestion immediately following contact, among its other effects. It was described as a similarity to the way a human's saliva immediately beings to break down starch.