CONSPECTUS AND CLASSIFICATION OF THE PLOCEINE WEAVER‐BIRDS

SUMMARY1 Apart from Amblyospiza and Neospiza , the Ploceinae fall naturally into two groups, A consisting of the Ploceus spp. of Sclater (1930), together with his Malimbus, Nelicurvius, Notiospiza and Anaplectes , and Group B consisting of Quelea, Foudia (except sakalava) and Euplectes in the broad sense of Delacour & Edmond‐Blanc (1933), together with Brachycope. Anomalospiza is included purely for lack of alternative. 2 Past classifications of the Group A birds are tabulated and discussed. Their disagreements, on affinities, on the use of super‐specific categories and on order, are very great. 3 The Group A plumages are described and discussed. The prevalence of dull (“nondescript”) female dress, of dull non‐breeding dress in the male and of polygamy is correlated with the dryness and seasonal variation of the habitat; consequently the type of dress is not a character of taxonomic value. 4 The Group A nests, unlike those of Group B, have an unequalled complication of protective devices in construction and in siting; but on the present information about them their characters cannot be utilized for taxonomic purposes. 5 The eggs of the Group A species (unlike those of Group B) show exceptionally high individual variation, which suggests that in their variously protected nests they are not subject to severe selection. Clutch‐sizes are discussed. 6 The beaks of the Group A birds do not fall so readily into categories that they could be used for taxonomic purposes. All the species with the most slender beaks are primarily insectivorous. 7 Size and proportions are discussed. The tail /wing ratio is in some cases consistent between species that on other grounds are regarded as very closely allied, and in other cases it is not. 8 The wing‐formula is discussed with special reference to the reduction of the outermost primary. Proportions of this feather do not seem to be correlated with habitat and they vary markedly between some birds that are very closely allied. But the extent of the reduction is to some extent characteristic of groups within the Ploceinae–in nearly all Ploceus and Malimbus spp. to 22–39% of wing‐length, in Euplectes species to 10–20%, in Foudia spp. to 21–26%, in Quelea spp. to 12%. 9 The Group B Ploceinae are in some respects less varied than the Group A and the great development of tails in some species has, as stressed by Delacour & Edmond‐Blanc (1933), been given too much taxonomic weight. 10 Group B eggs, in comparatively vulnerable nests, show no such individual variation as Group A eggs, but are of two distinct types that may have taxonomic correlations. 11 General topics are discussed: the much greater wealth of Ploceinae in East Africa than in the rest of that continent; the extent to which the Ploceinae have invaded islands; the overlap of species that are prima facie in competition; peculiarities of specific distribution; and intraspecific variation with particular reference to Bcrgmann's and Gloger's rules. 12 In a group like the Ploceinae classification should be in large genera, with informal species‐groups. Further, within the genus it is as a rule impossible to arrange most of the species in order of supposed “primitiveness” with any conviction. Similarly, no linear order of the Ploceinae can be devised that is not misleading. Both the genera and the species within each genus can more conveniently and less tendentiously be arranged alphabetically. In the order that follows, it should be borne in mind that the affinity of Ploceus to Malimbus and of Foudia to Euplectes is especially close. Among the species, the same numeral is suffixed to those which are regarded as belonging to the same species‐group.