AUSTRALIAN SKUA. 
show that the young is scarcely separable in coloration from the New Zealand 
C. lonnbergi, being uniformly blackish above and deep blackish-grey below. 
Yet the adult birds are very different and certainly worthy of specific 
recognition. In this case it is easily seen that living in the ice regions has 
brought about the light condition of the species. 
The specimens noted by Eagle Clarke above seem to be the only ones 
known from any other than the type-locality. 
Wilson recorded that variability in size was met with in the long series 
he had and gave detailed measurements, as wing $ 16.5-15.3, ^ 16.4-15.0. 
I find that the short ones are due to the fact that the primaries have not 
finished growing. It is interesting to notice that Cones {Bull. U.S. Nat. Mus., 
Vol. II., p. 75, 1875) wrote, “ Second primary longest.” This was due to 
the same cause, as when the wing is fuUy grown the first primary is clearly 
the longest. 
The two specimens procured by the Scottish Antarctic Expedition would 
seem to belong to a smaller race, as though the primaries are undoubtedly 
fully grown they measure under 400 mm. while adult typical birds go over 
this limit. 
Though there are only two specimens I consider they should be called 
Catharacta 7)iaccor7nicJci wilsoni, subsp. n. 
1 would point out that this differs from the typical form exactly as the forms 
of C. lonnbergi do from the respective northern localities. 
In the case of the Great Skuas, then, I should think that it might be 
considered that Catharacta skua antarctica (Lesson) might be compared with 
Phcebetria fusca fusca (Hilsenberg), but the form that would correspond to 
P. f. ca7npbelli Mathews is unknown. 
In their ranges Catharacta lonnbergi Mathews and Phcebetria palpebrata 
(Forster) appear to synchronise, but Catharacta 7naccor7nicki (Saunders) would 
be a form which has become specialised through its Antarctic living, and no 
form of Phcebetria has yet taken up that life. In this phase Macronectes 
giganteus (Gmelin) shows a better parallel, as a light form of this species exists 
at South Victoria Land and another light form also breeds at Graham’s Land 
and the South Orkneys. These have however not become so distinctly fixed 
as have the Skuas. ^ 
These Antarctic breeding birds vdll furnish a lot of interest for a long time 
to come, as we do not yet know anything of the bird-life of the Antarctic 
Continent between about Victoria Land and Graham’s Land and the South 
Orkneys. As I have indicated before, we know very little about the birds 
which are met with on the west coast of South America, and the Chilian Skua 
adds another. This beautiful form has not yet been traced to its breeding 
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