McCORMICK'S SKUA. 65 



No. 74, <J, ad. sk. Mar. 15, 1903. McMurdo Sound. 



75, <J,ad. sk. NOT. 27, 1902. 



76, <J,ad. sk. Mar., 1903. 



77, 9 , ad. sk. Feb. 24, 1904. Cape Adare. 



78, 9 , ad. sk. Jan. 31, 1902. Weathered and white. 



79, <J , ad. sk. Jan. 20, 1903. McMurdo Sound. 



80, <J,ad. sk. Jan. 15, 1903. 



81, 9 , ad. sk. Dec., 1902. 



82, $ , ad. sk. Jan. 15, 1903. 



83, <J , ad. sk. Nov. 27, 1902. 



84, ?, ad.sk. Dec., 1902. 



85, 9 , ad. sk. Dec., 1902. 



86, $ , ad. sk. Dec., 1902. 



87, ? , ad. sk. Nov. 27, 1902. 



88, 9 , ad. sk. Feb. 8, 1903. 



89, <J , ad. sk. Dec., 1902. 



Nos. 167-169, ad. skeletons. McMurdo Sound. 



225-229. Young Nestlings in Spirit. Cape Royds. 



230-234. Young Nestlings in Spirit. Cape Adare. 



Many eggs of this bird were taken, and preserved in "clutches," and singly, from Cape Adare, 

 Cape Royds, Cape Crozier, etc., at various dates during November, December, and January. 



The colouring of the soft parts is as follows : 



Bill of the nestling, bluish grey, gradually darkening to black as the bird attains to 

 maturity. Bill of the small adult, black. 



Iris, dark brown at all ages. 



Legs, toes, and webs, pale bluish grey in the young when just hatehed, gradually blacken- 

 ing from the extremities upwards, until, when the bird is full-fledged, the feet and 

 legs are black except for a patch of bright blue just above the tibio-metatarsal joint. 

 In the adult, wholly black. 



Claws, black at all ages. 



NOTE ON THE ILLUSTRATIONS. 



Plate XII. represents the head of Megalestris maccormicki in five stages of growth. 



Fig. 1. The nestling, when first hatched, with the egg scale still attached to the upper bill. 



Fig. 2. The nestling at about two weeks, showing the rapid growth of the bill, and the change in its 



colour. 

 Fig. 3. The fledgling at about seven weeks, when the bird is just beginning to attempt the use of its 



wings. The down in this case (Skin, No. 72) is completely shed, and the plumage is soft and 



close, of a uniform grey, very different to what it would be in another week or two when the 



feathers have assumed the harder character of the adult, and are dark brown in colour. 

 Fig. i. Represents the head of a young adult in the first year, with but little attempt at the display 



of a yellow collar. 

 Fig. 5. Represents an adult bird with the bleached and whitened plumage, which characterises the 



bird at the end of the summer months, before the moult. 



Plate XIII. represents the feet of McCormick's Skua in various stages of growth. 

 Fig. 1. Of the nestling immediately after leaving the egg. 

 Fig. 2. Shows the encroaching blackness which gradually creeps up the foot and leg from the 



terminal border of the webs and claws. This is the foot of a bird at two or three weeks. 

 Fig. 3. A stage of colouring reached at the shedding of the downy plumage. 

 Fig. 4. The foot of a normal adult. 

 Fig. 5. The pied foot and leg of an abnormal adult. See p. 68 for reference to this figure. 



