ARCTIC TERN. 
a trifle wider in vittata. In macrura the outer web of the outer tail-feather is dark grey; 
in vittata it is light grey, or even white. Owing to the throat being dark grey in vittata 
the white line running from the lores, below the eye, to the nape, is more noticeable; in 
macrura this white line blends in with the white cheeks. 
In vittata from Kerguelen the shafts of the primaries, except the outer one, do not seem 
so ivory white. 
Egg dates. Northern Mackenzie : Thirty-two records, June 14th to July 7 16th ; sixteen records, 
June 23rd to July 5th. Maine and Nova Scotia : Twenty-six records, June 8th to July 21st; 
thirteen records, June loth to 23rd. Alaska : Twenty-two records, May 4th to July 1st; 
eleven records, June 14th to 27th (Bent). 
Nest. Generally a mere hollow in the sand, gravel or moss or in the rooks, about one inch deep by 
five in diameter. Occasionally a thin lining of dry 7 grasses is used, but an elaborate nest is 
rarely 7 or never seen. 
Eggs. Clutch two, usually (to three). Ground colour varies greatly 7 , from Brussels brown, dark 
olive-brown to water-green or pale olive-buff. The eggs are more or less irregularly spotted 
or blotched with the darker shades of brown and often there are underlying spots of various 
shades of brownish drab. Average measurements of 123 eggs, 41 mm. by 7 29.5. They 
are very 7 similar to the eggs of the Common Tern (Bent). 
Incubation 'period . Twenty-one days. 
Breeding-seaso7i. May 7 to July (Alaska to Maine). Only 7 one brood. 
Distribution. Breeding in the islands north of Scotland (in Europe to 50° north lat. and in Asia 
to 52° north lat.). North America, Iceland and all the circumpolar region and migrating 
southwards to South America, New Zealand (one occurrence) and to 74° South lat. (Weddell 
Sea) and probably 7 Ross’s Sea. 
This bird has been added to the New Zealand list by Oliver, as quoted, 
who says that one specimen only has been obtained in New Zealand; a bird 
in winter plumage having been shot by Mr. A. C. O’Connon at the mouth of 
the Waikanae River, in December, 1929. 
Now, about the name of this Tern ; in the Austral Avian Record, Vol. V., 
Nos. 2 and 3, p. 45, February 21st, 1923, Iredale and I discussed Pontoppiaam’s 
Danske Atlas, 1763, and pointed out that this was the basis of Brunnich, 
Ornith. Borealis, 1764. 
Pontoppiaam’s description of Sterna paradiscea is : “ It has long tail- 
feathers, and is pure black on the head.” So we decided that this was in¬ 
determinable, and with us agreed a majority of the List Committee of the 
British Ornithologists Union. 
Brunnich’s usage does not help us, as his diagnosis agrees well with that of 
the Roseate Tern. 
About macrura there can be no doubt. 
In Bent’s work, as quoted, are six photographs, showing the nest with eggs 
in three differing localities, one with the bird at the nest and two showing the 
young, and on pi. 91 a coloured reproduction of three eggs. 
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