CUCULIDA. 265 
Common Cuckoo, Cuculus canorus. We all know 
that the Common Cuckoo is a summer migrant 
arriving here about the middle of April and . 
departing in August or September; the old 
song limits its stay to August. 
“Tn April, 
Come he will ; 
In May, 
He sings all day; 
In June, 
He alters his tune; 
In July, 
He prepares to fly ; 
Come August, 
Go he must.” 
This bird has so many peculiarities, both of voice 
and habits, that it has attracted more attention than 
any other bird. The times of migration and changes 
in voice are tolerably accurately pointed out in the 
old verses I have quoted; but its very peculiar habit 
of placing its eggs in the nest of another bird, whose 
own young are invariably sacrificed to the rapacity 
of the young Cuckoo, has attracted much observation 
and given rise to many wild theories, amongst which 
I must place the theory of Dr. Baldamus (which gave 
rise to considerable discussion in the ‘ Zoologist,’ in 
which useful periodical his paper on the subject 
was translated), that the Cuckoo has the power of 
colouring her egg to assimilate with that of the bird 
in whose nest it is placed: indeed the fact, which is 
RA 
