Combine tapioca, salt, and boiling water. Cook over hot water until tapioca is clear. Wash pears. Remove cores. Steam until tender. Place pears in saucepan. Add sugar and 1/4 cup water. Cover. Simmer 5 minutes. Combine with tapioca and lemon juice. Pour into buttered baking dish. Cover with marshmallows. Bake in moderate oven (375 F) 20 minutes. 6 servings.
