138 BULLETIN 208, UNITED STATES NATIONAL MUSEUM 



pusillus, Melittophagus hullockoides, Phoeniculus purpureus, Rhino- 

 pomastus cyanomelas, Upupa ajricana, Campethera abingoni, and 

 Myrmecocichla aethiops. That this practice is not invariably followed 

 is attested by the fact that in a still larger niunber of cases no such 

 egg damage was observed. The damage, when damage is done, 

 looks more like bill peck marks than claw marks as the latter would 

 tend to produce longer and more irregular cracks and breaks than are 

 described in these cases. There still is much to be learned of this 

 matter as the variation in the experience of individual collectors is too 

 great to be "explained away." Thus, in Southern Rhodesia, Neuby- 

 Varty considers egg pecking to be so much the regular procedure that 

 the young honey-guide, on hatching, seldom has to contend with any 

 nest mates. Years ago Haagner and Ivy (1907b, p. 103) concluded 

 that "all the Honey-Guides break the eggs of the foster parent to 

 make room for their own, wherever possible." Yet other collectors, 

 also with considerable experience, have not noticed any such tendency. 

 That the pecking, when it occurs, is done by the adult and not by 

 the chick when newly hatched is proved by the fact that it exists prior 

 to the hatching of the honey-guide egg. To present the situation in 

 a more telling manner, it may be said that no case of egg pecking or 

 clawing is known for the lesser honey-guide (/. minor) in an equal 

 number of parasitized nests. It is conceivable that eggs of certain 

 species of hosts are more regTilarly pecked than others ; the number of 

 instances are too small in these cases to be of statistical significance 

 but they may be worth mentioning; thus, pecking of the hosts' eggs 

 occurred in four out of six parasitized nests of the hoopoe, Upupa 

 ajricana, and in only one out of eight nests of the pied starling, Spreo 

 bicolor (only nests with eggs were counted). If it should develop 

 that there is a real difference in the treatment different host species 

 receive, it would suggest two possibilities — that eggs of some species 

 are harder to puncture than others or that some individual honey- 

 guides are more prone to peck holes in the eggs than others and that 

 they have some degree of individual host specificity. 



In some of these instances of egg pecking the damage might almost 

 be dismissed as accidental due to the supposedly hiu"ried actions and 

 movements of the honey-guide, while in others it is clearly not a 

 casual, perfunctory matter but bears every mark of being a deter- 

 mined effort to destroy the potential viability of the host's eggs. 

 Thus, in one nest of an African hoopoe, Upupa africana, one of the 

 two hoopoe's eggs had no less than 12 peckings and the other had 4. 

 Most of the pecks had not gone through the inner membrane, but in 

 one of the eggs two peck holes, larger than the others, had penetrated 

 the membrane. 



