AVIAN GENUS CHRYSOCOCCYX 13 



that this tendency has been retained in all the species that have 

 arisen from that segment. 



On returning to our descriptive review of the genus, we come to a 

 gap between meyerii of New Guinea and the two Asiatic species, 

 maculatus and xanthorhynchus. This is a gap both in existing birds 

 and in geography, and it should be made clear that the existing species 

 on the two sides of the gap are related but not necessarily immediately 

 derivative. Both are expressions, similar in some ways and distinct 

 in others, of a trend toward brighter, more glittering plumage. The 

 two species of the Asiatic mainland are closely related to each other, 

 although the adult males are strikingly different in appearance, that 

 of maculatus being bright metallic-green above and that of xanthor- 

 hynchus, bright violet. The females of the two are more alike, but 

 are readily distinguishable; that of maculatus has the crown and hind 

 neck between cinnamon and pale chestnut, and the upper parts of the 

 body light, but bright, green ■\\dth a varying amount of coppery glints 

 and reflections; that of xanthorhynchus is bronze-green above, slightly 

 browner on the head and has all the upper wing coverts and many 

 of the dorsal body feathers banded with chestnut. Moreover, the 

 violet cuckoo is slightly smaller than the emerald one. The juvenal 

 plumages and the eggs of the two are very similar. The emerald cuckoo, 

 C. maculatus, is a monotypic species, kno\\Ti to breed in the Himalayas 

 from Kuman through Assam, southeastern Tibet and Szechwan, to 

 Hupeh, south to Yunnan, and Burma, migrating or wintering south 

 to India, Hainan, the Malay Peninsula, and Sumatra. The violet 

 cuckoo, C. xanthorhynchus, with three races (one of them of uncertain 

 status), occurs from Assam, southwestern Yunnan, and southern 

 Annam, south to eastern Bengal, the Malay Peninsula, Thailand, the 

 Andaman and Nicobar Islands, Sumatra, Lingga Archipelago, Java, 

 Borneo, and east to the Philippines (Luzon, Mindoro, Samar, Cebu, 

 Basilan, and [?] Palawan). 



Alone among all the species of glossy cuckoos, the Asiatic emerald 

 cuckoo, C. maculatus, has been said to have two distinct seasonal, 

 adult-male plumages. Ticehurst (in Stanford and Ticehurst, 1939, pp. 

 15-16) was the first to caU attention to this matter. He was aware 

 of the fact that in the earlier literature only one plumage was de- 

 scribed for the adult male, but he found that not only did the birds 

 undergo a complete postnuptial molt (as is normal for practically all 

 birds), but that in the new plumage the upperparts of the body were, 

 not bright green, but coppery-bronze and that the head, ear-coverts, 

 chin, throat, and upper breast became, not solid bright green, but 

 barred, similar in pattern to the rest of the underparts. He further 

 found that there was a less complete spring molt, whereby the solid 

 green of the breeding plumage was once more regained. 



