Observations on the Cuckoo. 469 
genious and amusing work, espegially in the 
section on instinct. I shall, ce ay in this 
instance, content myself with exhibiting the 
erroneousness of his opinions respecting 
the cuckoo; which will be best done by 
tracing the progress of an individual of this 
species, from its extrusion from the egg, till 
it arrives at maturity, or begins to propagate 
its kind; since an examination of its various 
means of acquiring information on those sub- 
jects which are of the greatest importance 
for it to know, will furnish the surest crite- 
rion of what is due to nature, and what to 
observation and tuition. Let us suppose then, 
that a cuckoo’s egg is hatched in the nest of 
a titlark about the middle of June. No 
sooner is the young bird disengaged from the 
shell, than a disposition to eject whatever 
happens to be in the nest with it begins to 
manifest itself ; and as young cuckoos increase 
in size and strength very rapidly, it is soon 
enabled to turn out the nestling larks, which 
are suffered to perish within a few inches of 
the nest, being entirely abandoned by their 
parents. Now to what cause, I would ask, 
must we attribute this extraordinary propen- 
sity, which shews itself so early? As titlarks 
do not possess it, and as old cuckoos, after they 
have deposited their eggs in suitable nests, 
