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produced by the same bird, are generally found in the same district. I give below some notes 

 from my friend Mr. Carl Sachse, which tend to prove this ; and Mr. Walter states that he found 

 three very peculiar small Cuckoo's eggs in Wrens' nests close to each other, the first nest being 

 about thirty paces from the second, the second about twice as far from the third ; and he found 

 a fourth similar egg in a Whitethroat's nest which was built between the three Wrens' nests. 

 The egg of the Cuckoo is deposited, not as is the case with many birds, early in the morning, 

 but at various times in the day, not unfrequently in the afternoon ; and it would seem that the 

 bird does not wait until the egg is ready to be deposited before seeking for a suitable nest in 

 which to place it, but she proceeds on a tour of investigation beforehand, and selects a suitable 

 foster-parent, and when ready goes with all speed to place her egg there, being sometimes 

 accompanied by a male bird, but more frequently not. Some observers state that the hen 

 Cuckoo always destroys one or more eggs of the foster-parent ; but this seems only occasionally 

 to be the case, and more frequently when her egg is placed in an open nest — in which case 

 she can sit on the nest to deposit her egg, and probably in sitting down will throw out some 

 of the eggs which are already in the nest. It has also with justice been accused of devouring 

 eggs ; for my friend Mr. Sachse has seen one do so. Even after her egg has been deposited she 

 has been known to revisit the nest and throw out eggs or young birds, never, however, her own ; 

 and the young Cuckoo will also, soon after it is hatched, evict its nest-mates from the nest. 

 When the nest is an open one the Cuckoo will deposit her egg when sitting on the nest ; but it 

 frequently happens that the nest selected is so placed that she cannot possibly get at it except 

 with her head, and the egg is then first deposited on the ground, and then taken into her bill 

 and placed in the nest. A nest which is already tenanted is not always selected ; for there are 

 undoubted instances on record where a Cuckoo's egg has been found in a nest in which the 

 foster-parent had not yet laid. It appears doubtful whether the female Cuckoo takes any further 

 trouble about her egg, except that, as already stated, she has been known to visit the nest and 

 destroy the eggs or young of the foster-parent. Von Tschusi-Schmidhofen gives, on the authority 

 of a forester, Mr. Amort, an account of a Cuckoo, when a nest containing her egg had been 

 taken, following the plunderer to his house and remaining near the house all the day ; but I 

 cannot help thinking that this account must be accepted with great caution, and I find no other 

 similar account on record. Many theories have been propounded with regard to the reasons 

 why the Cuckoo deposits its eggs in certain nests ; and the most reasonable appears to me that 

 the female Cuckoo will in preference deposit her egg in a nest of the same species as that in 

 which she has been reared. But, at the same time, in case such a nest is not readily available, 

 she will drop her egg in the first best nest that she can find ; and this only can account for a 

 Cuckoo's egg having been found in the nest of a Little Grebe. Salerne, in 1767, appears to have 

 been the first to publish the theory, started by a native of Sologne, that in many cases the egg 

 of the Cuckoo assimilates or bears some resemblance to the eggs of the foster-parent ; and the 

 notion has again more recently been independently brought forward by Dr. Baldamus, who, 

 basing his data on the eggs in his own collection, remarks on the general similitude between the 

 Cuckoo's eggs and those of the foster-parent. I have myself collected a considerable number of 

 Cuckoo's eggs, together with those of the foster-parents, and have examined similar collections 

 in many parts of Europe ; and I must say that I have generally found this to be the exception 

 and not the rule ; for I calculate that not one of five or six Cuckoo's eggs resembles the eggs 



