^"iQoI'l Barrett, Parasitical Habits in the Cuciilidce. ^Q 



which constitute its victims. Other members of the Ciiculidce, 

 especially some of the Australian species, do the same thing. 

 The salmon-tinted egg of the Pallid Cuckoo {C. pallidus) is fre- 

 quently found among a clutch of flesh-coloured Honey-eaters' 

 eggs ; the Narrow-billed Bronze-Cuckoo [C. basalts) favours the 

 Blue Wren {M. cyaneiis), with her tiny pink-spotted egg ; and 

 most wonderful of all is the Fan-tailed Cuckoo {C. fiabellifonms). 

 I have found a great number of the eggs of the last-named 

 species in nests of the White-browed Scrub-Wren {Sericornis 

 frontalis'), and in several instances the resemblance between the 

 eggs of foster-parents and Cuckoo has been most pronounced. 



It is thought by some naturalists to be highly probable that 

 the food eaten by birds during the nestling period has much 

 to do with the future colouration of their eggs, and, if such be 

 the case, it goes far to explain the similarity between the eggs of 

 many species of Cuckoos and those of their foster-parents, for it 

 follows that the latter would rear the alien chicks upon the same 

 food on which they would have fed their own offspring. The 

 stomach of a female Bronze-Cuckoo {C. plagosiis) shot at Olinda 

 Creek last September was found, on dissection, to contain the 

 remains of a number of the large green caterpillars of the cup moth 

 {Pelora) and the emperor gum-moth {Aniherea eucalypti). In 

 the oviduct was a soft-shelled egg, on which the beautiful bronze- 

 green tint characterising the eggs of this species was just be- 

 coming visible. I have watched closely several young Bronze- 

 Cuckoos being fed by Blue Wrens and various species of 

 AcantJiizce, and in many instances have noticed that the devoted 

 little nurses were attempting to satisfy the voracious appetites 

 of their charges with lepidopterous larvae of a greenish hue. 



With reference to a recently made suggestion that the action 

 of the infant Cuckoo in ejecting its nest-fellows is purely auto- 

 matic,* rhythmic, and governed by external stimuli or reflex 

 action, I still cling to the belief that the process is referable to 

 hereditary instinct or sub-conscious memory, aided by dawning 

 reason. I am strengthened further in my conclusions by com- 

 paring notes with other ornithologists in various parts of the 

 world. Mr. Edward Step, F.L.S., in his essay on " The Cuckoo," 

 distinctly states that " shortly after birth the young Cuckoo 

 shows that it has inherited the knowledge that its foster-parents 

 will have all they can manage to satisfy its own wants, and that 

 the presence of nest-fellows means overcrowding, and inevitable 

 death for the majority, should they be allowed to remain." My 

 friend, Mr. W. Percival Westell, M.B.O.U., a well-known British 

 ornithologist, who has devoted years of study to elucidating the 

 habits and life-history of the European Cuckoo {C. canorus), 

 writes that his observations lead him to credit the blind nestling 



* The Emu, vul. v., p. 145. 



