8 U.S. NATIONAL MUSEUM BULLETIN 2 65 



The term "locus of origin" must be accepted in a rather loose 

 sense, as we have no way of proving that the islands presently used 

 as wintering quarters Mere the original homes of these subsequently 

 migratory birds. It so happens that the main areas to which these 

 cuckoos now repair for their nonbreeding season, the Solomon Islands, 

 and, to a lesser extent, the Bismark Archipelago, have no resident or 

 breeding populations of glossy cuckoos. In the complete absence of 

 evidence as to what may have been the case in the remote past, it is 

 not possible to explain this geographical gap or even to ask if there 

 may once have been Chrysococcyx populations there. The current 

 absence of local birds may make these islands more readily "suitable" 

 for the New Zealand and Australian migrants, but even this suit- 

 ability is uncertain. In Africa the populations of the three species of 

 glossy cuckoos that breed in the southern portion of the continent 

 spend the southern winter in equatorial areas that contain resident 

 popidations of all three. It may be that the absence of breeding fantail 

 warblers (Gerygone) in the Solomons is correlated with the lack of 

 resident glossy cuckoos, for both this favorite host and its parasite 

 occur on Rennell and Bellona Islands. 



For the sake of greater coherence and clarity in this review of the 

 history of the differentiation and dispersal of Chrysococcyx, discussion 

 will be limited to species. The variations within each species mil be 

 treated later as needed. At this point it is sufficient to say that in no 

 case do the infraspecific variations and differentiations throw any 

 doubts on the vicissitudes, here outlined, of the specific taxon of 

 which they are a part. 



If we begin with the Indo-Malaj^sian area as the probable locus of 

 origin of the genus, C. malayanus A\'ould then seem to be the nearest 

 of the existing species to the original home area, as well as the one 

 most similar to the ancestral stock. As the most wide-ranging of the 

 Malaysian-Australian members of the genus, and as the most poly- 

 typic species of the entire group (with 11 races), it appears that 

 malayanus may well be the oldest of existing Chrysococcyx species. 

 It includes only tropical forms, most of \\'hich seem to be nonmigratory 

 as compared with the nearly related species lucidus and basalis, 

 parts of which are highly migratory. In their review of the subspecies 

 oi malayanus, Hartert and Stresemann (1925, p. 160) noted that from 

 the Malay Peninsula eastward the races of this species inhabit almost 

 all the islands of the Malay archipelago, east to New Guinea and the 

 Fergusson Islands, and to the tropical portions of Australia. In his 

 discussion of the origin of the avifauna of Timor and Sumba, Mayr 

 (1944, pp. 172, 189) considered C. malayanus as one member of the 

 "Banda Sea" element, a group of species of more eastern origin that 

 supposedly came into these islands in Pliocene time. The species is 



