THE CUCKOO’S SECRET 
162 
to the dummy nest, immediately taking out the 
remaining egg. She then turned round, sat length- 
ways on the nest, laid her egg in six seconds without 
the slightest effort, and flew swiftly away without 
sound. 
Were it not that I have proved that the Cuckoo 
finds the nests in which to lay by watching the 
foster birds building them, it would be remarkable 
that the Cuckoo should have known of this well- 
hidden Meadow Pipit’s nest, so well concealed that 
it would have done credit to a Grasshopper Warbler.* 
It is only, of course, when the nests are exceptionally 
well concealed that the Cuckoo has any difficulty 
in going to them when ready to lay. It is the best 
possible proof of the correctness of my theory that 
the Cuckoo first locates them when the fosterers 
are building, and then, when returning to lay, has 
no such direct guide to the exact spot. 
A curious incident happened at the taking of 
“ Mary Pickford’s ” sixth egg on May 31 soon 
after 4.10 p.m. She had laid her egg with three 
Meadow Pipit’s, taking one away as she did in- 
variably. Smyth replaced the eggs with three of 
another Meadow Pipit. At 7.30 p.m. Smyth and 
party returned to the nest to mark the substituted 
* Locustella naevia. 
