478 



8 



pass overhead a hissing noise is distinctly heard. Sheep-dogs, and even cattle when wandering 

 near their nests, are assailed with great vigour and driven from the vicinity. The nests are very 

 slight, in some cases consisting merely of the beaten-down grass, or at most of a few bents, and 

 are placed on the open moor. Though the birds breed in colonies, the nests are always a con- 

 siderable distance apart. It is almost impossible to find their eggs, except by chance, without 

 watching the bird to her nest, which in fine weather is rather a test of patience, as it is necessary 

 to lie in partial concealment until her fears are dissipated, which sometimes takes a considerable 

 time ; but in cold or wet weather the birds are very unwilling to leave their eggs, and, if 

 disturbed, soon return. The number of eggs never exceeds two, though a single one was found 

 much incubated." 



Eggs of this Skua in my collection vary in ground-colour from light or darker brownish 

 green to greyish green or olivaceous green, and are more or less spotted with deep umber-brown, 

 some having but few spots, whereas others are tolerably profusely spotted with blackish brown ; 

 and in almost all there are a few deep-purplish grey shell-markings. In size they vary from 2^- 

 by Iff inch to 2f§ by Iff inch, and are ovate-pyriform in shape. 



Mr. Collett says (Orn. Norw. p. 114) that " the food of this species varies considerably, 

 according to the season of the year. In the spring and autumn it probably consists to a great 

 extent of fish, which it takes from the Gulls and Terns ; in the summer it subsists mainly on 

 insects and sea-fowl eggs. In the stomachs of individuals shot in Nordland and Finmark in June 

 and July I found coleoptera, especially Elateres and Harpali, and also Tipulidae ; and in others I 

 found, besides insects, fragments of egg-shells ; but I seldom discovered any remains of fish. The 

 eggs of the Eider Duck in particular are the objects of their depredations ; hence they are every- 

 where regarded as a noxious bird, the sworn enemy of every 'iEgvser ' proprietor. This hungry 

 marauder wages endless war with all other sea-fowl. The Terns, however (Sterna fluviatilis and 

 hirundb), and Larus canus fiercely repel its predatory attacks ; and even Strejpsilas interpres will 

 muster up courage for a fight should it venture to encroach upon its territory." In South Africa, 

 where Mr. Layard has had excellent opportunities of watching this bird, it constantly, he says, 

 sits on the water and swims about, hunting for food, and he has shot at it more than once in the 

 act of doing so. The first specimen he shot was out of a flock sitting and swimming in Table 

 Bay. 



The adult bird above described is figured on the same Plate with Buffon's Skua ; and on a 

 second Plate I have figured the dark form and a young bird in the mottled plumage, — both being 

 the specimens above described. 



In the preparation of the above article I have examined the following specimens : — 



E Mus. H. E. Dresser. 



a, 6 . Faeroes, April 28th, 1874 (Schliiter) . b, c, d (light form) . Greenland (Erichsen) . e (dark form) . 

 Greenland. / (light form) . Ofjord, Iceland, 1871 (A. Benzon). g, ? (light form) . Archangel, June 10th, 

 1874. A, d (dark form). Archangel, June 10th, 1874 (Piottuck). i (light form). Labrador (Moschler). 

 k (light form). Bay of Fundy (G. A. Boardman). I, m (dark form). N. America [S. F. Baird). n,juv. 

 St. Michael's, N. America (S. F. Baird). o (light form). HudsonVBay Territory (Capt. Blakiston). 

 p, pull. Hoy Island, 1867 (Dunn), 



