The Arundinacea are taxonomically the most difficult group of Sorghums. Snowden (1936, 1955) subdivided them into 28 cultivated and 24 related wild “species”, but it is now generally agreed that his cultivated species are best regarded as cultivars. DeWet & Huckaby (in Evolution 21:787-802. 1967) pointed out that since there are no genetic barriers between any of the taxa, wild or cultivated, they should be treated as a single species. This view is perhaps a little extreme and there are sound practical reasons for maintaining the cultivated Sorghums as a separate species from the wild ones. Indeed, it seems best to regard the Arundinacea as comprising two polymorphic species, one cultivated (Sorghum bicolor) and the other wild (Sorghum arundinaceum). In Africa, however, the obvious convenience of such an approach has its drawbacks because there is continuous introgression between the two species, and the desirability of having a third, hybrid taxon (the oldest applicable name being Sorghum drummondii) is apparent. While Fl hybrids are clearly Intermediate, F2’s begin to show segregation and the boundry between the wild and cultivated Sorghums easily becomes heavily obscured.