Punching fast and furiously, I would beat the daylights out of them until they were bloody all over.

Take Powder of Fænugreek, Aniſeeds, Cumin-Seeds, Elicampain, Colts-foot, Flower of Sulphur, of each three Ounces, Juice of Liquorice one Ounce, Oil of Olives, and Hony, of each eight Ounces, Genoa Treacle twelve Ounces, Oil of Aniſeeds one Ounce; mix altogether, with a Pound and a Half of Wheat Meal, or what is ſufficient to make the whole into a Paſt, which roll into Balls as about as big as a common Waſh-Ball.

They remain within the intermediate host until it is eaten by the definitive host.

The human is so poorly designed for aquatic adventures that he cannot even see in the water without artificial aids.