8 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 124 



two of the hosts but not to those of the commonest one. Even this 

 seems somewhat doubtful. 



Yellow -billed Cuckoo: Cuculus canorus gularis 



The hosts of the African yellow-billed cuckoo, as stated earlier 

 are less well known than are those of its congeners. To date, so far 

 as I have been able to learn, the only fosterers for which there are 

 more than single records are the drongo, Dicrurus adsimilis; the bou- 

 bou, Laniarius jerrugineus; and the fiscal shrike, Lanius collaris. Two 

 of the following list, the bush shrike {Malaconotus zeylonus) and the 

 robin chat (Cossypha caffra), were listed as hosts by Levaillant over 150 

 years ago and have not been so reported by anyone since then. They 

 may be considered, therefore, as indefinite, especially since they were 

 not documented in detail by their reporter. The absence of more 

 recent records would be cause for scepticism in the case of a better 

 known species of cuckoo ; in this case there are so very few observations, 

 one can hardly claim that the old pioneer of African cuckoo studies 

 has or has not been contradicted. 



The recorded or reputed hosts are as follows : 



records records 



Dicrurus a. adsmilis (Bechstein) 3 Lanius collaris Linnaeus 4 



Pycnonotus barbatus tricolor Cercotrichas p. paena (Smith) 1 



(Hartlaub) 1 C. leucophrys pactoralis (Smith) 1 



Lamprotornis species 1 Cossypha caffra (Linnaeus) 1 



Laniarius Jerrugineus 3 Passer griseus diffusus (Smith) 1 

 Malaconotus z. zeylonus 



(Linnaeus) 1 



It is of interest to note that, unlike its two African congenors, this 

 cuckoo does make some use of nests in holes in trees, as shown by the 

 instances of the glossy starling and the gray-headed sparrow. It may 

 be recalled that Haydock (1950, pp. 149-150) in Northern Rhodesia 

 saw a pair of an unidentified species of Lamprotornis feeding a recently 

 fledged red-chested cuckoo. Because it is known that adult birds of 

 many species often react with food to the clamorous importuning of 

 fledgling birds that they have not reared themselves, this record is 

 not included in our list of hosts of Cuculus solitarius. The fact that 

 the yellow-billed cuckoo has been found to lay in a nest of a glossy 

 starling may lend probability to the nature of Ha3 7 dock's record, but 

 it still remains uncertain. In its use of shrikes' and of drongos' nests 

 as repositories for its eggs, the yellow-billed cuckoo does compete 

 with the jacobin cuckoo, but the latter parasitizes drongos very 

 seldom. 



Eggs of three types have been described for the yellow-billed cuckoo : 

 pale greenish blue with pale mauve and brown spots; light bluish gray 



