ABSTRACT
The distribution of birds in Africa south of the Sahara is now comparatively well documented, both specifically and subspecifically. The most significant features of avian geography in Africa concern the distribution of birds of the evergreen forest. "Montane evergreen forest above about 1300 m. usually differs from its lowland counterpart in floristic composition, in the abundance of epiphytic bryophytes, and in the smaller height of the trees. In tropical Africa typical montane forest exists, at least vestigially, on most mountains that rise much above 5000 feet (at much lower altitudes near the sea). The lowland forest of West Africa is divided into two blocks, west (Upper Guinea) and east (Lower Guinea) of the "Dahomey gap" which runs approximately between Accra and Lagos and is almost entirely savanna. Hence the climatic change that would permit west-to-east communication of these lowland East African animals could not coincide with the change required for the montane birds.
