It is well settled that a shipment of freight imposes an obligation to pay charges according to the established rates for its transportation. Any charge not in conformity with such rates is illegal, and there is no estoppel against the collection of undercharges. Estoppel would result in discrimination by indirection, and the law forbids discrimination under any circumstances. This applies to the consignee as well as the consignor. Pittsburg &c. Company v. Fink, 250 U. S. 577; New York Central &c. Company v. Company, 256 U. S. 406. “The obligation of the consignee to pay the charges of transportation commonly rests on acceptance of the goods when the transportation has ended. That obligation is *529 coextensive with the charge legally due, no matter what may be the statement of that charge by the 'carrier.” American Ry &c. Co. v. Mohawk Dairy Co., 250 Mass. 1, 9.

Exception overruled.