Cambridge Monographs in African Archaeology 73 The region traditionally known as the M ma is a plain of deep alluvial deposits that lies west of the current seasonally flooded Inland Delta of the Niger River and southwest of the Lakes Region. The M ma is also sometimes referred to in the literature as the 'Dead Delta', a name that evokes the presence of a dense network of dry watercourses. This indicates that the M ma once formed a...