32 The late Dr. Jenner 
upon the latter merely as visitors ; and let it be recollected 
how soon the visits of some of them are paid ; for being go- 
verned by an unerring principle, they stay to accomplish one 
great design only, that of rearing their young, and then 
return. 
The countries to which many of the winter birds retire not 
being very far distant, are better known to us than those to 
which the summer birds migrate ; but I must forbear enter- 
ing into an enquiry upon this subject, as remote from the 
design of this paper ; and indeed it may be thought I have 
already, in some instances, digressed too widely from my 
original purpose. 
The migration of the winter birds is less distinctly marked 
than that of the spring migrators. The snipe, the wild- 
duck, the wood-pigeon, breed herein considerable numbers ; 
the two latter indeed, particularly the wood-pigeon, are so 
numerous in summer, that we should hardly be reminded of 
the migration, did they not pour in upon us in such immense 
flocks in the winter. They are accompanied by the stock- 
dove, which I have never known to breed here. The home- 
bred wild-ducks are easily distinguished by the men who 
attend decoy-pools, by the meanness of their plumage, when 
compared to the brightness of those birds which come from 
abroad. The former are taken some weeks earlier than the 
latter. 
The most conspicuous among the winter migrating birds 
are the redwings and fieldfares. These are regular and uni- 
form in their appearance and disappearance, and I believe 
never risk the trial of incubation here, at least I never could 
hear of a single instance. The food of these birds has in the 
