32 U.S. NATIONAL MUSEUM BULLETIN 2 65 



highlands from Kumaon through Assam, southeastern portions of 

 Tibet, and Szechwan to Hupeh, and south to Burma, Yunnan, and 

 Annam. It has been recorded in winter or on migration in India, 

 Hainan, Cochinchina, the Malay Peninsula, and Sumatra. The violet 

 cuckoo, C. xanthorhynchus, occurs from Assam, southwestern Yunnan 

 and southern Annam, south to eastern Bengal, the Malay Peninsula, 

 Siam, Cochinchina, the Andaman and Nicobar Islands, Sumatra, the 

 Lingga Archipelago, Java, Borneo (including Banguey Island), the 

 Natuna Islands, and the Philippines (Luzon, Mindoro, Samar, Cebu, 

 and Basilan, possibly Palawan). Being a small bird of the treetops, it 

 generally goes unobserved; several observers have told me that it was 

 only occasionally that they found or collected this cuckoo. 



These two small, brilliantly colored cuckoos seem in every way so 

 closely related that it is somewhat unexpected to find that they differ 

 as they do in their migratory behavior. It seems that xanthorhynchus, 

 with a geographic race, amethystinus, in the Philippines, and another 

 possibly dubious one, bangueyensis, on Banguey Island off the north 

 shore of Borneo, may originally have been more of a geographic 

 expander than maculatus, but that its outlying populations became 

 sedentary and, in time, became subspecifically differentiated. 



The yellow-throated cuckoo, C. flavigularis, is a nonmigratory bird 

 of the western African forests. The other three African species are all 

 partly migratory — regularly so in their southern populations, all of 

 which regularly desert their South African breeding areas at the close 

 of the season and pass the nonbreeding months in the tropical portions 

 of the continent. 



Of the remaining three African species, C. Haas is the least con- 

 sistent in its migratoriness. The didric, C. caprius, and the yellow- 

 bellied emerald, C. cupreus, have very definite dates of arrival and 

 departure in Africa south of the Zambesi, bvit Haas is considerably 

 less precise. Thus, Clancey (1964, pp. 221-222) \\Tote that in Natal 

 and Zululand Haas was "almost wholly migratory, the majority only 

 on the southern breeding grounds between the months of September 

 and April . . .," but that many overwinter there. Similarly, Benson 

 (1940, p. 402; 1942, p. 212) was aware of even a greater percentage of 

 overwintering individuals in Nyasaland, which caused him to con- 

 clude that in that country Haas had no regular migration. In eastern 

 equatorial Africa, in Kenya and Uganda, Jackson (1938, pp. 503-509) 

 concluded that Haas was subject to partial or local migration. Although 

 it is not clear from his account if part of his apparent uncertainty of 

 the bird's local seasonal movements was due to the annual arrival of 

 "wintering" birds from South Africa, this might have been the case. 

 Farther north, in Ethiopia, Benson (1942, p. 212) found klaas to have 

 no regular migration, as contrasted with caprius. White (1965, p. 186) 



