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on the migration of birds. 
The winter birds of passage, as they are commonly called, 
begin to take their leave of us about the same time that the 
spring migrators are taking wing to pay us their annual visit. 
As the latter appear among us in gradual succession, so in 
like manner the former disappear. They are both actuated 
by the same impulse, the former in leaving, and the latter in 
coming to this country, namely, the enlarged state of the 
testes and ovarium. As soon as the stimulus becomes suffi- 
ciently felt, they quit their homes in quest of a country better 
suited to their intended purpose than their own. 
That a want of food cannot be the inducement, must be 
obvious to the slightest observer. When the redwing and 
fieldfare quit this country, it abounds with that food which 
they prefer to any other ; and at this time they are in the 
finest condition ; the redwings often enjoying their plenty by 
assembling together on trees, and there uniting their feeble 
voices, make no unpleasant song.* 
The winter birds (the females at least) may be said to 
seek a better accommodation, upon the same principle as the 
poor woman who quits her cottage for the comforts of a 
Lying-in Hospital. Here, both herself and suckling are for 
a while supported in that peculiar way which their situations 
at that time require. For this reason, conceiving it will tend 
to lessen confusion, I choose to call this country the home of 
the winter birds (though not natives ) , and the countries from 
whence they come, the home of the summer birds, looking 
* The same thing happens through the winter, whenever the weather has long 
continued so mild as to allow them plenty of insect food. The starling, and some 
other birds which have a short note and weak voice, unites with its companions in 
the spring, and forms a similar concert. 
