19 1 7'] Bre€trin[/-hnhits of tJie Cuckoo. 209 



Cuckoo was laying, by rather exposing to view nests of the 

 Hedge-Spariow, and making the owners desert, and then 

 ]eavit)g an incomplete or complete clutch in the nest for 

 some time, but 1 have never obtain-ed a Cuckoo's egg in 

 such nests. 



Possibly the nest and the foster-parents by which she 

 herself was reared may both have some effect on the 

 Cuckoo, and we may suppose that, if she cannot find a 

 nest in which the eggs resemble her own, she then places 

 her egg preferably in the nest of that species by which 

 she herself was reared. 



My view is that the Cuckoo, whose whole nature seems 

 careless and improvident, lays her eg^ in some suitable spot 

 xind also very often leaves it there, with perhaps a second or 

 third laid subsequently, and then commences a search for 

 nests in which to deposit them. In any case, after laying 

 her first egg the Cuckoo would be able to recognise the eggs 

 of other species which resembled her own more or less 

 closely, and this would explain the large proportion of the 

 eggs which resemble the general type of those of the foster- 

 parent. Those that do not, are presumably due to inability 

 to find a suitable nest. 



It seems to me far more likely that the Cuckoo is 

 influenced by the colour of the eggs in the nest more than 

 by the actual nest itself or the birds to which it belongs, 

 though it seems possible that she would be attracted by the 

 locality and surroundings in which she herself was reared, 

 and would seek nests in a similar ])lace. 



Moreover, one may "conclude that, to avoid causing alarm 

 ,and being '' mobbed " she would endeavour to examine the 

 selected nests while the owners were away and thus might 

 not see the foster-parents, in which case she could not be 

 influenced by them. 



The main point, therefore, on which further information 

 is required seems to me to be whether the nest is selected 

 before or after the egg is laid, and this is exceedingly 

 difficult to obtain. 



SER. X. VOL. V. p 



