LIFE AND BEHAVIOR OF THE CUCKOO 
209 
than which nothing seems to arouse the parent, and especially 
the female, to quicker attack or bolder measures. When touched, 
however gently, the little bird spreads its wings, stiffens, and lies 
flat with every quill and feather erect (fig. 11) and it repeats these 
defensive measures as often as it is touched or disturbed. After 
recovery from such a state it will bound out of its nest as often 
as it is returned, and for all such nest-life is at an end. (Compare 
p. 206.) If the nestling reaches the ground it is difficult to follow 
it, and even more difficult to recover the bird when once it has 
found any grass or shrubberJ^ 
Under these circumstances the behavior of the old bird, es- 
pecially if a female, is equally interesting. She is on the spot 
in a moment, and flies low, often coming close to the head of the 
intruder, giving a peculiar mewing sound, like a catbird, and an 
equally peculiar note, like kek-kek-kek, punctuated with the same 
high-pitched explosive alarm heard in the young, or flipping the 
wings, spreading and pumping the tail, breaks into the more 
ordinary alarm, — Ker-ut-ut-ut, with the last syllable bitten off 
particularly sharp. With excitement at its height a brisk snap- 
ping of the mandibles is heard, while at a lull, the bird will stop 
to preen. 
10. THE CLIMBING STAGE 
With about half of its feathers freed in the way described, usu- 
ally on the seventh or eighth day, the young cuckoo suddenly 
leaves its nest, and enters upon a climbing stage, (fig. 8) which 
lasts until flight or for at least fourteen days (table 6) . The act is 
interesting, and since it has been repeatedly seen when performed 
under natural conditions, and by three birds in succession in one 
instance I will describe the procedure in the case of the oldest bird 
(table 6, bird no. l,nest no. 3). With the sun shining full, but 
not excessively hot, this cuckoo crawled to the far side of its plat- 
form, combed off several mouthfuls of feather-tubes, and sat bolt 
upright; then directing its attention to a small branch, which 
rose from under the nest, it begun to duck and raise its head, much 
as an old bird might do when preparing for flight. Presently it 
THE JOURNAL OF EXPERIMENTAL ZOOLOGY, VOL., 9, NO. 1. 
