272 
LIST OF BIRDS 
But it is not alone by facilitating our knowledge of ex- 
ceptions to general and received facts in this very interest- 
ing science, and guarding us against the allurements of 
premature generalization, that the steady pursuit of this 
branch of zoology paves the way to its advancement : cer- 
tain countries, from the peculiarity of their circumstances 
and g-eographical situation, furnish opportunities for ascer- 
taining what may be regarded as the pure and general 
characteristics and habits of the species that frequent them ; 
experience in such favourable situations is then of directly 
general application, and hence the communication of its 
results becomes proportionably more interesting. The 
Zetland Islands, in relation to most of their zoological ob- 
jects, are precisely in this state ; and from the peculiar 
facilities which they afford to the researches of the natural- 
ist, combine in themselves one of the most select stations for 
generally applicable and accurate observation and experi- 
ment, in this department of natural history. For the study 
of ornithology they are singularly adapted, and especially 
for that branch of it that refers to sea-fowl, which in many 
other countries are usually so difficult of access. Irt these, 
Zetland is peculiarly rich for variety and number: and 
though its land-birds are comparatively few, chiefly per- 
haps from the absence of woodlands, yet, as far as they 
extend, they are of equal interest. 
The birds more commonly found in these islands have 
been long since described by authors as inhabiting them. 
The following list is, therefore, supplementary to theirs, 
containing fifty-nine additional species that I have met with 
in this country, few of which are, I believe, generally 
known to occur in it. They are either permanent inhabi- 
tants, annually migratory, or occasional visitants. 
