THEORIES AND CONCLUSIONS 229 
the fact that the only two occasions — in 1920 and 
1921 — when the Cuckoo laid in a nest other than 
that of a Meadow Pipit, were also the only two of 
her “ laying-days ” in those two seasons on which 
there was no suitable accommodation within her 
territory, i.e. no Meadow Pipit’s nest, with eggs 
unincubated, on the common. To my mind this 
is one of the most valuable discoveries of the whole 
inquiry, as it suggests that a dominant Cuckoo, 
even at the expense of being compelled to forsake 
her regular foster birds, prefers to lay within the 
confines of her own territory, rather than seek 
further afield for suitable nests of her regular 
fosterers. Territory, in short, takes precedence 
% over foster bird. 
Moreover, this discovery and the theory of 
dominance seem to me to be mutually corrobora- 
tive. A dominant Cuckoo, mistress of her own 
territory after (presumably) a struggle with com- 
petitors, prefers to remain on her own ground and 
dupe a bird of some species other than her usual 
foster birds, because she knows — I think one may 
legitimately say — that if she begins to wander she 
will soon come into conflict with another hen 
Cuckoo dominant over another territory. 
