PALLID CUCKOO. 
observation .... on visiting the nest one morning we beheld a blind and 
naked nestling, easily recognised by its larger size as the Cuckoo, in the act 
of ejecting one of its foster-brothers from the nest The Cuckoo we 
judged to be about thirty hours old, while the young Wrens had probably been 
hatched a few hours earlier. We were able to secure a good picture of the 
young murderer at work, because on one of the Wrens being replaced in the 
nest, the Cuckoo at once proceeded to throw it out again, with the result that, 
during the two hours of our watching, he accomplished this feat no less than 
six times. Struggling desperately until it succeeded in getting the feebly 
resisting Wren into the hollow of its back, and balancing it there with extended 
embryo wings, the young Cuckoo, with head bowed between its strong legs, 
which, with claws firmly fixed in the sides, were straddled across the nest 
worked its way gradually to the entrance, and on this being reached, suddenly 
raised the head and with a sharp upward hft of the body pushed the 
unfortunate nestling over the edge. His work accomplished, the young 
usurper gave a final shrug of the body, as if to make certain his burden was 
gone, and subsided exhausted to the bottom of the nest. It has been 
suggested that the chief factor which operates on the young Cuckoo, and 
causes it to throw out its foster-brethren, is probably involuntary muscular 
action, incident on local irritation of the nerves of the skin when in contact 
with a naked nest lin g, I scarcely think the facts warrant us in accepting 
this theory without some reservation ; for, if it has much in its favour, it still 
leaves unexplained a most important point, viz., the reason why a distinct 
hoUow should be present in the back of a Cuckoo during the nestling period, 
and disappear in the adult bird, if not specially adapted by natural selection 
for the function it so admirably performs. Again, no one who has not actually 
witnessed the scene can realise the deliberate and apparently reasoning 
manner in which a young Cuckoo commits his crimes. Cuckoo nestlings are 
very voracious. I have often watched them being fed, and found it no 
uncommon thing for the devoted little foster-parents to make over thirty 
visits within an hour to the nest with food for their charge. The menu is 
varied, but the larvae of lepidopterous insects form an important item, as 
far as my observations go. The young bird develops rapidly on this diht, 
and the nest soon becoming too small for his increasing girth, expands to 
nearly twice its original size, and even then is filled to bursting point. The 
Cuckoo is fed by the foster-parents long after it has quitted the nest, in the 
vicinity of which it remains for some time, its plaintive cry for food being 
always responded to by its anxious guardians. While in the nest the Cuckoo 
displays a viciousness in keeping with its general character, for if one’s finger 
be placed within reach it will be fiercely pecked until withdrawn.” 
VOL. vn. 
297 
