Appellees brought these suits to restrain the enforcement of a statute of Iowa known as the “Chain Store *33 Tax Act of 1935” (Iowa Code of 1935, c. 329 G-l). The District Court, composed of three judges, held that the provision of § 4 (b) of the statute, imposing a tax based on gross receipts from sales according to an accumulative graduated scale, was invalid under the equal protection clause of the Fourteenth Amendment of the Constitution of the United States as creating an arbitrary discrimination. 12 F. Supp. 760. The case comes here upon direct appeal from a final decree granting a permanent injunction. 28 U. S. C. 380.

The decree is affirmed upon the authority of Stewart Dry Goods Co. v. Lewis, 294 U. S. 550.

Affirmed.