services normally provided for remuneration and shall in particular include: (a) mainland cabotage: the carriage of passengers or goods by sea between ports situated on the mainland or the main territory of one and the same Member State without calls at islands; (b) off-shore supply services: the carriage of passengers or goods by sea between any port in a Member State and installations or structures situated on the continental shelf of that Member State; (c) island cabotage: the carriage of passengers or goods by sea between: - ports situated on the mainland and on one or more of the islands of one and the same Member State, - ports situated on the islands of one and the same Member State; Ceuta and Melilla shall be treated in the same way as island ports.