Bus routes in Staten Island all originally took the prefix R- for the borough of Richmond. This was changed to S-, probably about the time that the borough was officially named Staten Island (1975). Around 1989, the route numbers were changed. The listing below is ordered by the original numbers, with the new numbers shown as well. The largest street railway company in Staten Island was originally the Richmond Light & Railroad Co. In addition, the Staten Island Midland Railway operated a few routes.