10 U.S. NATIONAL MUSEUM BULLETIN 265 



color on the basal portion of the next three pairs. However, this 

 character of rufous coloration in the tail feathers varies considerably 

 within the species malayanus, and since lucidus (and its races) and 

 malayanus (and its numerous subspecies) do not overlap geographically 

 in the breeding season, it may not be too farfetched to ask if they may 

 not be conspecific, representative forms. Thus, within malayanus, all 

 the rectrices have rufous in the race inhabititing northern Queens- 

 land, C. TO. russatus, while in C. to. minutiUus there is no rufous in 

 the outermost pair of rectrices, although there is a considerable amount 

 of this color in the basal half of each of the next three pairs; in C. to. 

 rujomerus there is no rufous in any of the tail feathers; in C. to. malay- 

 anus there is no rufous in the outermost pair, although a considerable 

 amount in the basal portion of the next two pairs. 



The species C. basalis not only has a narrower bill but also differs 

 in other proportions, such as the longer tail and somewhat longer legs. 

 It also is less bronzy colored above than malayanus or lucidus and its 

 throat is longitudinally striped or streaked, rather than barred as in 

 the latter two. It is more distinct from either malayanus or lucidus 

 than they are from each other. Also, that lucidus and basalis are 

 sympatric is further evidence of their specific distinctness; as said 

 above, however, this geographic argument does not apply to the 

 lucidus-malayanus picture. 



At this point we come to a much more noticeable morphological 

 differentiation, a change that resulted eventually in the species oscwZaws. 

 Here the striking change is in the loss of the metallic, glossy coloration 

 in this bird, which is othermse a larger relative of lucidus, basalis, and 

 malayanus. The eggs of malayanus are said (by North, 1912, p. 28) to 

 approach a chocolate-bronze color at times. It is possibly significant 

 that the eggs of C. osculans are a rich chocolate-brown color; this may 

 reflect some phylogenetic connection betAveen the two, osculans being 

 a glossy cuckoo that has lost its glossy color but is otherwise an obvious 

 member of the group. However, egg coloration in parasitic cuckoos is 

 too selectively vulnerable and, hence, changeable in the course of 

 evolution to be, in itself, a very trustworthy index of relationship. 

 The most that may be said of osculans is that it is more probably 

 related to the other Australian congeners (lucidus, basalis, and malay- 

 anus) than to any of the other, geographically more distant species of 

 Chrysococcyx. 



We now come to two derivative species foimd in the mountains of 

 New Guinea, rujicollis and meyerii. The former is, essentially, fairly 

 similar to malayanus but has the throat and breast suffused with 

 rufescent. This poses no difficulty in a phylogenetic reconstruction 

 since malayanus (especially the subspecies C. m. russatus) shows a 

 trend in this direction. C. rujicollis, still a poorly known species, occurs 



