Contained within the Atlas of Canada 8.5x11 series maps is a map which was created as a joint effort by The Atlas of Canada, The National Institute of Statistics, Geography and Informatics, Mexico and the National Atlas of the United States under the sponsorship of the commission for environmental cooperation. The map shows the major North American drainage basins, or wateresheds, which drain into the Atlantic Ocean, Hudson Bay, the Arctic Ocean, the Pacific Ocean, the gulf of Mexico and teh Caribbean Sea. Each watershed is shown in its own colour, with subdivisions shown in tonal variations. Areas of internal drainage, which lack outlets to the sea, are shown in grey.