3 ® 
THE CUCKOO’S SECRET 
Visiting it on July 5 it contained B 1 plus four eggs 
of the Meadow Pipit about three days incubated. 
The facts concerning this nest will be recalled later, 
as they provide contributory evidence both as to 
Cuckoos visiting nests before depositing and in 
support of a theory which I shall elaborate on 
“ dominant ” Cuckoos. 
In another Meadow Pipit’s nest I found B 2 
with three eggs of the fosterer, all some four days 
incubated. These two eggs discovered to-day 
were all that were seen of Cuckoo B during this 
season, and it will be noticed that she did not begin 
to lay until Cuckoo A had finished. It will be 
further observed that although there were many 
Skylarks, Tree Pipits and other species of small 
birds on the common, no egg of either of these 
Cuckoos was found in any but nests of the Meadow 
Pipit. 
Date when 
egg found. 
Summary of 
No. of 
egg. 
the 1919 Investigation 
Cuckoo A 
Presumed 
date of 
Fosterer. laying. 
Presumed 
order of 
laying. 
May 18 
A 1 
Meadow Pipit 
May 18 
I St 
„ 22 
A 2 
yy 
„ 20 
2nd 
„ 22 
A 3 
yy 
„ 22 
3rd 
„ 28 
A* 
yy 
„ 24 
4th 
„ 28 
A 3 
yy 
„ 26 
5th 
„ 3 i 
June 3 
A 6 
yy 
„ 30 
6th 
A" 
yy 
June 3 
8th 
„ 8 
A s 
yy 
„ 7 
10th 
„ 12 
A 9 
yy 
,, 1 
7th 
