6 
president’s address. 
explanations have been given; one is that the cuckoo destroys 
one of tlie eggs in the nest before depositing her own to 
ascertain if the clutch is fresh. I think this is probable, as I 
have often found egg shells in proximity to a nest containing 
a cuckoo’s egg, evidently destroyed by some bird. Another 
explanation is that the cuckoo watches the nest being built, 
and as soon as the first (one or two) eggs are laid then 
deposits her own, as after incubation had commenced she 
would have little opportunity of effecting her purpose, the 
intended foster parent being rarely absent from the nest. 
The belief held by many, that the cuckoo is able to produce 
an egg closely resembling those in the nest sbe contemplates 
making use of, is so illogical that if it were not for the 
wonderful similarity in colouring often observable between 
the cuckoo’s egg and those belonging to the nest, it would 
soon die out ; but quite as great contrast is also found. If 
the cuckoo had this power of discriminating colour, it is 
certain that after laying the egg and ascertaining the peculiar 
tints she would have to carry it about either in mouth or 
feet until she found a clutch of analogous hue. 
Now, when we consider that the cuckoo cannot know the 
colour of her egg until it is extruded, supposing one lays an 
egg very like a meadow pipit’s and deposits such egg in a 
nest of that species, it is very likely that in that same neigh¬ 
bourhood several instances will be found of this close resem¬ 
blance, which is easily accounted for, as the cuckoo lays about 
four or five eggs, if not more, in the season ; and I also have 
no doubt that all laid by the same bird are alike in colouring, 
and in case pipits’ nests were plentiful, I see no reason why 
the cuckoo should wish to exert herself in finding others; 
hence we should get a number of examples of this close 
similarity of colouring. 
I will give you an instance that came under my notice 
which clearly proves that a bird lays eggs always alike in 
colour and markings. Two years ago my father showed me 
a clutch of blackbirds’ eggs in a spinney near his house, of 
unusual coloration, having all the markings collected in a 
band or zone at the larger end, instead of being speckled all 
over. I took these eggs, but, unfortunately, they were hard 
set, therefore did not make good specimens for the cabinet; 
about three weeks later, I was informed that the same pair 
of birds had nested again, and upon putting the old bird off 
her nest, I found a clutch of eggs exactly like those I had 
previously taken. 
(To be continued.) 
