Chromosome studies were made in 33 specimens of the genus Galago, referable to the following seven species and subspecies: alleni, crassicaudatus crassicaudatus, crassicaudatus kikuyuensis, crassicaudatus monteiri, demidovii, senegalensis ssp. and senegalensis braccatus. The chromosome numbers and karyotypic structures found in these (sub)species are reported and described. Of six of them idiograms were constructed. All other available data on the cytology of the Galagidae are reviewed.The intraspecific variation of the karyotypic structure in crassicaudatus and senegalensis was found to be clearly correlated with the subspecific identification of the specimens studied. The chromosome number variation in senegalensis braccatus (2n = 36, 37 or 38) however, is most probably a true genetic polymorphism, due to the translocation of an acrocentric chromosome to the short arms of a subtelocentric one. The karyological relationships within each of these two species is discussed.An extensive discussion is dedicated to the karyological relationships between the four Galago species hitherto cytologically studied. It was found that, based on the chromosome measurements carried out, the remarkable chromosome number difference between crassicaudatus (2n = 62) and senegalensis (2n = 38) can possibly be explained by postulating the successive occurrence of 24 centric fusions or translocations of whole acrocentric chromosomes in an original common karyotype, by which the chromosome number would have been reduced from 62 to 38. Because of its low diploid chromosome number (2n = 40) and its relatively high number of larger biarmed autosomes, the karyotype of alteni is probably closely related to that of senegalensis, though its exact position is not yet clear. The position of the karyotype of demidovii is also doubtful, but the high number of chromosomes (2n = 58) of which only six are submetacentrics seems to indicate that many original characteristics have been preserved in this karyotype. All possible karyological relationships are represented in a scheme.
LEOBERT E. M. DE BOER
Karyotypic descriptions are given of 16 species of Accipitridae new to cytology, viz. Torgos tracheliotus. For reasons of comparison the karyotypes are included of 5 species that have been previously studied, viz. Gypaetus barbatus, Haliaeetus albicilla, H. leucocephalus, H. vocifer and Pernis apivorus. All these species share the typical characteristics of the accipitrid karyotype, a moderate diploid number (66-72), the absence of large macrochromosomes, the presence of only 6-12 microchromosomes and a high number of mediumsized to small macrochromosomes. Differences exist in the numbers of biarmed and acrocentric autosomes and in the size and shape of a pair of typical satellited marker chromosomes.The karyological relationships in the Accipitridae are briefly discussed. On the basis of the morphology of the pair of satellited chromosomes (acrocentrics, subtelocentrics or microchromosomes) and the numbers of acrocentric elements nine possible phylogenies are constructed. When compared to conventional phylogenetic trees for the Accipitridae, the following points are remarkable in all possible karyological phylogenies: (1) the position of Pithecophaga is uncertain, it either represents an independent ancient lineage or is related to the Old World vultures; (2) Gypaetus probably is not related to the Old World vultures, it rather evolved from an ancester in common with the booted eagles; (3) genera like Buteo, Geranoaetus and Accipiter may have evolved independently from the booted eagles; and (4) the kites probably do not constitute a natural group.
The karyotypes of 7 species of Psittaciformes new to cytology are described: Cacatua galerita, Caly_pto-rhynchus magnificus and Probosciger aterrimus of the Cacatuidae, and Ara macao, A. ararauna, Amazona viridigenalis and Psittrichas fulgidens of the Psittacidae. For reasons of comparison the karyotype of Melopsittacus undulatus is also described. These karyotypes are compared to 8 psittaciform karyotypes previously recorded. There is a remarkable heterogeneity of karyotypes in the Psittaciformes. Nevertheless, it seems possible to recognize Cacatua, Calyptorhynchus and probably also Probosciger (Cacatuidae) by their karyotypes as a dearly related group. The karyotypes of these cacatuids also bear some resemblance to that of Loriculus (Psittacidae). The psittacid genera Amazona, Ara, Nestor, Melopsittacus, Psittaeula, Psittacus and Psittrichas are karyologically heterogeneous, but their karyotypes show certain relationships. The karyotype of Brotogeris is very different from those of other psittacids.
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