This leaves the formation of higher terms entirely unknown, and shows nothing beyond the quinary or non-quinary character of the system.

Still, among those which Stanley, Schweinfurth, Salt, and others have collected, by far the greatest number are decimal.

As our knowledge of African languages is extended, new examples of the vigesimal method may be brought to light.

But our present information leads us to believe that they will be few in number.
In Asia the vigesimal system is to be found with greater frequency than in Europe or Africa, but it is still the exception.

As Asiatic languages are much better known than African, it is probable that the future will add but little to our stock of knowledge on this point.