A New Mexico statute exacts a flat permit fee for the privilege of transporting motor vehicles, on their own wheels, over the highways of the state, for purpose of sale within or without the state. Held, this does not impose an unconstitutional burden on interstate commerce nor does it discriminate against a citizen of another state engaged in transporting automobiles on their own wheels, in processions or caravans, for sale outside of New Mexico. Morf v. Bingaman, (U.S. 1936) 56 S. Ct. 756.