Num 7:7-9

7Two wagons and four oxen he gave to the Gershonites, according to their service;8and four wagons and eight oxen he gave to the Merarites, according to their service, under the direction of Ithamar son of Aaron the priest.9But to the Kohathites he gave none, because they were charged with the care of the holy things that had to be carried on the shoulders.