Interstate vs. intrastate commerce

It is undoubtedly true that the question whether commerce is interstate or intrastate must be determined by the essential character of the commerce, and not by mere billing or forms of contract. ... But the fact that commodities received on interstate shipments are reshipped by the consignees, in the cars in which they are received, to other points of destination, does not necessarily establish a continuity of movement, or prevent the reshipment to a point within the same state from having an independent and intrastate character.