THE HONEY-GUIDES 103 



The few data available include but two records of more than one 

 egg being deposited in any one nest. In these cases there is no certain 

 way of telling if the multiple honey-guide eggs were laid by the same 

 bird or not, but inasmuch as in one of those two cases one of the eggs 

 was considerably longer than the other it would seem probable that 

 two hens were involved. Contrasted with these two cases we have 

 records of single honey-guide eggs in four other cases, as well as 

 inferential single eggs in an additional four or five other nests. In no 

 case is there any evidence of any pecking of the host's eggs. Indi- 

 cator variegatus agrees in this respect with /. minor and not with /. 

 indicator. 



Nothing is known of the incubation period. 



Hosts or Victims 



Considering the enormous geographic extent and the great ecological 

 variety of the range of the scaly-throated honey-guide, the known 

 victims of its parasitism cannot be looked upon as anything more than 

 the merest beginning of a definitive list of its hosts. Meager though 

 the recorded data are, it may be noted that all of the known victims 

 are hole-nesting birds. Of the 12 species of birds involved, 5 (1 with 3 

 subspecies) are woodpeckers, 4 are barbets, 1 is a swift, 1 a thrush, and 

 1 a weaver finch. Two of the barbets cannot be considered established 

 definitely as hosts, while the records of another of the barbets, of 3 of 

 the woodpeckers, the swift, the thrush, and the weaver finch all leave 

 something to be desired in one way or another to make them completely 

 certain. This leaves 1 barbet and 4 woodpeckers as the only birds 

 unquestionably known to be victims of Indicator variegatus. The 

 absence of records for any of the bee-eaters and starlings — common 

 birds, many of whose nests have been found — suggests that in the 

 choice of its victims this honey-guide is more like /. minor than /. 

 indicator. (See accounts under each of these species, pp. 139-154, 

 192-204.) 



Micropus horus (Heuglin). Horus swift. 



Cypselus affinis var. horus Heuglin, Ornithologie Nordost-Afrika's . . . , 

 vol. 1, p. 147, 1869. (Northeast Africa.) 



One record. 



The identification (by John G. Williams) of the honey-guide egg 

 "almost certain," but admittedly by inference rather than by direct 

 evidence. A. W. Vincent found a nest of this swift in the Kidong 

 Valley, Kenya Colony, at the foot of the escarpment on the main 

 Nairobi-Naivasha road on May 21, 1950, containing two eggs of the 

 swift and one of the variegated honey-guide, the latter measuring 21 

 by 15.4 mm. The three eggs were in about the same stage of incuba- 

 tion, being very slightly set, with a little veining. The swifts, as is 



