ARCTIC SKUA. 
Mr. Charles Belcher tells me that it “ may be seen following in the wake 
of steamers in Port Phillip Bay at almost any time of the year ; it is easily 
distinguishable by the projecting centre tail-feathers. It has never been known 
to breed in Australia.” 
Stejneger* says : On the Commander Islands the dark form is the most 
common. A few only with white lower surface were seen, and one secured. 
This species is found mostly on Bering Island where it breeds on the great 
tundra, or rather swamp, near the village. In 1883 the first ones made their 
appearance on the 4th of May. In the autumn they seem to feed to a great 
extent on the berries of Empetrum nigrwriy and their excreta at that time are 
colored dark blue. The natives call them by the Russian name ‘ Basbojnih' ” 
Meddendorff records it from on the Boganida and the Taimyr River. 
The bird figured and described was collected in Alaska on August 
30th, 1897. 
From a careful consideration of the facts relative to this species, the 
well-known dimorphism would seem to supply a northern equivalent to the 
southern cases of Macronectes giganteus (Gmelin) and the Antarctic Skuas. 
Instead of long series from definite localities, however, we have only uncon- 
nected observations which, unfortunately, mostly miss the points that need 
most investigation. It however seems certain that the further north the 
bird breeds the fewer dark birds are met with, while in the southern breeding 
localities only a small proportion of light birds, and those somewhat piebald, 
occur together. If inquiries were carried out on these lines we should learn 
something about the species. At the present time the series available are from 
scattered localities, and generally atypical — i.e. the dark birds are shot from 
light colonies and the light ones from dark colonies. The plumage changes 
are quite unintelligible on account of lack of material, and need much study. 
Whether the piebald birds breed true or not is as yet unknown, and from the 
specimens I have examined the light-breasted bird breeding in northern climes 
is not mixed with dark birds at all. This would seem to be the case all round 
the Subarctic Zone, and a most interesting study seems to have been entirely 
neglected by northern ornithologists. 
It has been proved that this species, known as S. crepidatus Gmelin or 
Banks, is the true L. parasiticus of Linne. As there has been controversy as to 
the exact status of Gmelin’s name, which was primarily founded oU Banks’s 
nude name, it becomes appropriate to reproduce Solander’s detailed description 
prepared from the specimen noted by Banks : — 
crepidatus Larus supra nigricans cinereo-undulatus, subtus cinerascens fusco-undulatus, pedibus 
albidis : membrana nigra basi alba 
♦ Bull. U.S. Nal. Mua., No. 29, p. 86, 1885. 
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