Patterns of distribution, diversity and endemism for 1595 species and well‐marked subspecies of Afrotropical (excluding marine islands) passerine and non‐aquatic non‐passerine birds are identified and analysed using uni‐ and multi‐variate statistical methods. Patterns of distribution are well predicted by a hierarchical model of African avifaunal zones based on patterns of distribution and evolution in guineafowl (Family Numididae). The boundaries of avifaunal zones recognized here for passerines and non‐passerines are similar to one another, and largely parallel those of broad contemporary vegetation types along a rainfall gradient. However, there are interesting discrepancies between the distributions of contemporary vegetation types and inferred avifaunal zones, most notably the disjunct similarity of the avifaunas of three sections of lowland forest, much of which presently is an apparently continuous belt. We interpret this disjunct avifaunal similarity in the light of palaeoecological and geomorphological data as evidence in favour of the hypothesis of forest refugia. This hypothesis states that presently continuous forests were fragmented during arid conditions in the geological past, and that birds which prefer forested biotopes were confined to “island” forest refugia. Patterns of diversity and endemism, when considered together with patterns of distribution, also support the refugium hypothesis, and suggest the existence of two additional refugia, one in the western African forest, the other in the eastern African equatorial savanna. Several of these refugia may have been important centres of evolution for forest and open country birds.

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The Brown Mussel (Perna perna) is an important fooditem for coastal people in the Republic of Transkei, providing some 16% of their annual protein requirements in 1978, though the energy benefit associated with the consumption of Mussels is relatively low. Uncontrolled heavy exploitation of the stocks of these Mussels resulted in reductions in both their density and size between 1978 and 1984. The reduced availability of Mussels to collectors led to increased exploitation-pressure on other, longer-lived, intertidal species: the proportion of limpets in the take of collectors rose from 7% in 1978 to 37% in 1984, while the proportion of Brown Mussels decreased from 92% to 57%.

ASSTRACT.-We studied restriction-fragment length polymorphisms (RFLPs) in mitochondria! DNA for 13 species of African franco!ins (Francolinus spp.) and the Japanese Quail (Coturnix c. japonica). Phylogenetic analyses of RFLPs for these 14 species and of morphological and behavioral characters for the 41 francolin species and other perdicine taxa do not confirm the monophyly of Francolinus as currently recognized. Analyses of morpho-behaviora! characters suggest that Francolinus consists of at least four major assemblages: the five Asiatic species; two groups of African quail-like species; and the African partridge-like species. Within these assemblages, analyses of RFLPs and/or morpho-behaviora! characters support the monophy!y of six of eight species groups attributed to Francolinus. Assuming the monophy!y of currently recognized supraspecific groups of ga!!iform birds, morphometric analyses of gal-!iform skeletons correctly classified 90-99% of specimens to family, subfami!y and tribe, as well as 95% of the francolin specimens to genus. Genetic distances derived from RFLP data imply that African francolins diverged from their sister taxa at or before the mid-late Miocene, and that a!! species studied diverged from their sister-species during the Pliocene or early Pleistocene.

The vascular anatomy of the head and neck of eight adult helmeted guineafowl (Numida meleagris) was investigated by latex injections and dissection, resin casting, and lipidol injections and X‐ray photography. The vascular anatomy of these regions is similar to that of the domestic fowl Gallus domesticus, the main differences being in the helmet, wattle and cere vascularization, and the presence of a nape‐cheek rete in N. meleagris. It is postulated that five vascular arrangements in the head and neck are important in brain temperature regulation. These arrangements are: the nape‐cheek rete, the temporal rete, fine arteriovenous networks in the wattles and cere, and the cavernous sinus‐intercarotid association. All but the last of these arrangements require pathways of blood flow to the brain other than the most direct route. Such pathways are discussed.