AVIAN GENUS CHRYSOCOCCYX 33 



summarized the data by calling the species "largely resident, but 

 evidence of migratory movements in some areas . . , ." 



Klaas's cuckoo has been divided into three races, but one of these, 

 arabicus, knowm from very slight and unsatisfactory material, is only 

 doubtfully distinct; the other local race, somereni, from coastal 

 northern Kenj^a, seems more valid, but it is yet to be agreed upon by 

 all students of African ornithology. White (1965, p. 186) recognizes 

 neither arabicus nor somereni. A widely distributed species such as 

 klaas, largely resident in much of Africa from Senegal east to the 

 Sudan, Ethiopia and Somalia, south to Angola, Southern Rhodesia, 

 and the eastern Cape Province, might have become differentiated 

 into local races with minor morphological characters, but it has not; 

 somereni of north Kenya coastal belt is the only (and small) segment 

 of the total continental population that has become even slightly 

 different (more pronounced white edgings on the wing feathers). Its 

 uniformity can, however, hardly be attributed, even to a small degree, 

 to the partial migratoriness of Klaas's cuckoo. 



From the phylogeny suggested earlier in this report of the species 

 of glossy cuckoos, it would seem probable that klaas was originally 

 a forest bu'd lil^e its close relative flavigularis. Its extension throughout 

 the bushveld and the tree-dotted parklands of much of Africa was a 

 secondary expansion. Only in the southern i^art of that expanded 

 range has it encountered seasonal changes marked enough to encourage 

 migratoriness. 



The other two African glossy cuckoos, cupreus and caprius are 

 essentially similar in their seasonal movements to Haas, but, in 

 caprius particularly, their migration is more definite. Certainly in 

 areas south of the Zambesi the birds are present only in the breeding 

 season, arriving in October, and leaving in late April or early May. 

 In Natal Clancey (1964, pp. 220-221) found cupreus and caprius to be 

 sunamer residents (October to April) A\'intering in equatorial Africa, 

 with caprius arriving slightly earlier than cupreus. In other parts of 

 Africa there are movements correlated vdth the rainy season. In my 

 earlier account (1949a, pp. 154-156) I noted that caprius was reported 

 as present in Sierra Leone only during the rains, arriving late in April, 

 and that in northern Nigeria its arrival was noted at the beginning 

 of the rains late in May. In Darfur caprius arrived in June and re- 

 mained until September; in Ethiopia it was also noted to occur only 

 during the rains, all birds having departed by the end of May. All 

 this suggests that the didric population of northeastern Africa shifts 

 about, to what location no one knows, at the time when the southern 

 breeding birds are flying northward. In Nyasaland it is a local migrant, 

 and in Zanzibar the resident population is increased by an influx of 

 birds in October and November. 



