NO. 4 AVIAN GENUS CLAMATOR — FRIEDMANN 85 



reason why pica may not produce an occasional melanistic individual 

 as serratus does in such numbers, although breeding examples of 

 such have not been found as yet. If the Gabon, Lake Chad, Darfur, 

 and Ethiopian black examples are looked upon as pica, where do 

 the black serratus go when they leave their breeding range? If they 

 are serratus, why have so few of this phase been collected during 

 the southern winter while so many more of the pied phase have 

 been taken ? The discrepancy in numbers of winter specimens of the 

 two is not at all consistent with their numerical status (almost equiva- 

 lence in some localities) in southeastern Africa during the southern 

 summer. Is it possible that the bulk of eastern serratus, which would 

 include most of the black morphs, migrate a relatively short distance 

 into Mozambique, an area where relatively little collecting has been 

 done, and where Lamm (1955, p. 33) found this cuckoo (recorded 

 binomially by him, but almost certainly serratus) from December 

 through February? The only evidence, if it may be called that, sug- 

 gesting that some of the melanistic serratus from southeastern Africa 

 may wander far beyond Mozambique, even as far as southern Ethiopia, 

 is that Mearns (in Friedmann, 1930, pp. 272-274) not only collected 

 one bird, already mentioned, at Sagon River, on June 4, but saw four 

 there, June 3 to 6, and two others at Turturo, June 15 to 17. If 

 Mearns was correct in his identification of these sight records, this is 

 the only instance known of a substantial, as opposed to a casual or 

 individual, movement of these dark serratus. It is certainly not likely 

 that the breeding pica of southern Ethiopia frequently produce melanic 

 morphs in a limited area, or we would have had some other evidence 

 of it by now, and, hence, if these records of Mearns are accepted 

 they must be looked upon as migrant serratus. In support of this 

 latter interpretation it may be noted that Mearns collected two ex- 

 amples of the pied plumage phase of serratus at Gato River, near 

 Gardula, southern Ethiopia, April 7 to 8, together with other examples 

 of the white-breasted race pica (ibid., pp. 268-272). That pied 

 morphs of serratus could reach southern Ethiopia as early as April 

 7 suggests either a very rapid migration, which is not very likely, 

 or that some of the southern birds must start north considerably 

 before others. 



In Southern Rhodesia, where we might expect to find the black 

 phase with some regularity either as a breeder or as a migrant, M. P. 

 S. Irwin informs me that he has never seen one in life, and that the 

 collections in Bulawayo contain a single Southern Rhodesian example, 

 taken at Forest Vale, near Bulawayo, on November 20, and another 



