DIOMEDEA CHIONOPTERA. 



inner, median and greater coverts pure white, forming a wing-patch which adjoins 

 the white bases of the secondaries. 



A tinge of pink or rose-colour on the face or neck is sometimes seen in adult birds, 

 but the reason of this has not yet been explained. 



I have not seen the young of this species, but Mr. Hall describes it in three 

 stages of plumage. One, he says, was dark on the crown of the head, the back not 

 being pure white, but resembling that of D. exulans ; another phase was quite 

 brown, with a little white on the face, while a third was blotched with sombre colour 

 on its neck. On the 2nd February, 1898, Mr. Hall obtained a specimen at sea 

 (Lat. 43° S., Long. 102° E.), which he considered to be in an intermediate stage 

 between the uniformly brown young bird and the almost mature white-necked one. 

 He describes it as follows : — " Dark brown, except the bill, face, cheeks and throat, 

 which were white, with two white lines of feathers on the wings close to the body, 

 as it floated on the water ; the under-sides of the wings had two bands of bluish- 

 white and black. It was a piebald bird, most likely of the last season, late in its 

 moult, but not so late as the very brown one." 



It will be noticed that these three stages of plumage are very similar to those of 

 D. exulans, viz., a uniform brown, a white-faced brown, and the white-winged, white- 

 backed stage. The full plumage is not acquired for some years, and even when the 

 white- winged adult dress is attained, it appears that the back shows a few zigzag bars 

 on some of the feathers, and another stage must be gone through before the pure white 

 back is assumed. Dr. Reichenow, writing of D. chionoptera, says that the species 

 requires further study in order to prove whether it is really distinct or only D. exulans 

 in its most aged plumage. 



Layard describes a nestling brought from the Orozets by Captain Armson, 

 as " covered with pure white silky down," said to be about five or six days old 

 (Layard, Ibis, 1867, p. 460) ; this white down, it will be remembered, is one of 

 the specific characters of D. regia, to which D. chionoptera is very closely alhed. 

 The same author says that the bill was the most remarkable feature, " the tips of the 

 mandibles being armed for about three-quarters of an inch with obtuse tumid 

 sheaths, as hard, white, and shining as china." 



The specimen described is the type from Kerguelen Island, and the figure is 

 taken from the same bird. 



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