CATHARACTA ANTARCTICA. 
Eggs. Clutch two in number, and similar in type to those of the other 
large Skuas. They have a character of their own and in a series are readily 
distinguishable from the eggs of the Lari of similar size, but the differences 
are somewhat difficult to describe. They are, however, as a rule more pointed 
in shape than most Gulls’ eggs. Surface rather glossy but texture coarse. 
Markings generally somewhat sparse ; never so heavily blotched as most of 
the Gulls’ are occasionally. Ground-colour ranges from greyish-buff to olive- 
brown, sometimes with a tinge of reddish, with spots and blotches of sepia- 
brown or vandyke-brown, sometimes very dark and a few underlying ashy- 
grey markings, but as a rule not numerous. 
Measurements of eggs from the Falklands : c/2 : 74.5 by 49.3, 74 by 51 ; 
68.1 by 49.7, 72 by 50.8 ; c/2 : 72.6 by 50, 68.5 by 52.1 ; 73 by 49.7 ; c/2 : 
69.5 by 50, 69.7 by 48.2 ; c/2 : 74.2 by 50.4, 72.6 by 48.1 ; c/2 : 68.7 by 50, 
72.1 by 50.3. Average size of 13 eggs from the Falklands : 71.5 by 49.9 mm. 
Maxima: 74.5 by 49.3 and 68.5 by 52.1 Minima: 68.1 by 49.5 and 
72.6 by 48.1. 
A number of eggs from the Tristan da Cunha group are very similar. 
Average of 7 eggs from the Tristan group : 71.98 by 50.9 mm. Maxima : 
80.3 by 51.5 and 68.4 by 53 mm. Minima : 66.4 by 50.1 and 76.2 by 49.7. 
Breeding-season. Eggs in the Falklands are laid from the end of November 
onward through December. 
In the South Orkneys the birds returned on October 21st and the first eggs 
were found on November 27th. 
Two eggs from the South Orkneys are figured in the Ornithology of the 
“ Scotia ” (Scottish National Antarctic Expedition), Plate VI. (Vol. IV.). One 
egg is also figured in the Catalogue of the Eggs in the Collection of the British 
Museum, Vol. I., pi. xviii., fig. 5, but, as is unfortunately the case with all the 
plates in this work, it is not stated from which locality the figure is taken. 
C is tic ola juncidis, ante, p. 125, pi. 45. 
Nest. A very beautiful and remarkable structure, often compared to a 
purse, or the gossamer home of some large spider, or the elongated, sausage¬ 
shaped web of a host of caterpillars. It is quite unlike a bird’s nest. 
Constructed chiefly of down from grasses with a certain amount of fine 
grass interwoven, and bound together with cobwebs. It is well-concealed in 
the middle of thick grass or rushes, and is woven to the stalks ; very elongated 
in shape, perhaps four or five inches from top to bottom, and two or three 
inches in diameter at the widest part. It narrows at the top and bottom, and 
near the top is the entrance hole, not well-defined. 
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