AVIAN GENUS CHRYSOCOCCYX 31 



Guinea and the islands to the west of it. Because it does not cross 

 great expanses of open water its migration may seem less spectacular 

 than that of typical lucidus. Yet it would seem likely that much of the 

 vast expanse of the arid country of the Australian interior would offer 

 little to a bird of passage and that plagosus may well cover much of it 

 without pausing. 



The other two races of C. lucidus are nonmigratory, C. lucidus 

 layardi in New Caledonia, the Loyalty Islands, New Hebrides, Banks 

 and Santa Cruz Islands; C. lucidus harterti in RenneU and Bellona 

 Islands. 



The next species, C. basalis, is highly migratory. It breeds in Tas- 

 mania and southern Australia and "winters" in the Sunda Islands 

 from Java to Sumbawa, but has been recorded also from the Malay 

 Peninsula, Sumatra, Borneo, the Natuna and Kangean Islands, 

 Christmas Island (in the Indian Ocean), and Celebes; it has been noted 

 on migration in the Aru Islands and in the Cape York Peninsula. It 

 appears from the above that it veers generally farther to the north- 

 west in its northern, postnuptial journe3ang than does C. lucidus pla- 

 gosus, with which it is largely sympatric as a breeder. 



Since the next species, C. ruficollis, is nonmigratory, we pass on to 

 the following one, C. osculans, which is at least partially migratory. 

 The literature on this point gives the impression that, at least in 

 southern Australia, the bird does definitely leave its breeding range 

 at the end of the season, returning there at the start of the next one. 

 Gilbert (1935, p. 22), wrote that in New South Wales the black-eared 

 cuckoo was regularly and ''completel}^ migratory." By ''completely" 

 he apparentl}^ intended to convey the thought that its migration was 

 more definite and obvious to the local observer than was that of 

 basalis and lucidus (plagosus), both of which species he described as 

 incomplete, but regular, migrants. Peters (1940, p. 28) was unable to 

 learn much about osculans, writing that the extent to which it is mi- 

 gratory was uncertain, but noting that it had been recorded from the 

 Aru and Kei Islands and from Batjan. It appears to ''winter" in the 

 Moluccas, according to van Bemmel (1948) and Mayr (1953), also to 

 a considerable extent in northern Australia. Being essentially a bird 

 of drier areas than the other species of Chrysococcyx, it may winter as 

 well in parts of central Australia, where its presence would be undis- 

 closed since there are no observers to report it. 



The New Guinea mountain species, C. meyerii, is apparently non- 

 migratory, even in an altitudinal manner. Coming now to the two 

 Asiatic species, C. maculatus and C. xanthorhynchus, the former is 

 definitely migratory, the latter possibly slightly or only partly so. 

 Even where xanthorhynchus is migratory, its movements are largely 

 unrecorded. The little emerald cuckoo, C. maculatus, breeds in the 



