COMMON SKUA. 481 



The bill is black, tingled with greyish-blue ; the iris 

 brown ; the feet black, the claws bluish-black. The ground 

 colour of the plumage is deep greyish-brown ; on the breast 

 and abdomen passing into brownish-grey. On the upper 

 part of the head the feathers arc slightly tipped Avitli yellowish- 

 brown ; on the neck their acuminate terminations are brown- 

 ish-yellow ; on the back a considerable portion of each is 

 light reddish-brown, on the scapulars is a larger irregular 

 variegated whitish patch. The wing-coverts are less marked ; 

 the primary coverts and quills are brownish-black, with their 

 shafts white unless toward the end, and a large portion of 

 their base of the same colour, which thus forms a conspicuous 

 patch on the wing, but does not extend to the outer web of 

 the outer quill, and is not apparent on the seventh. The 

 secondaries gradually become lighter, the inner being brown. 

 The tail-feathers are blackish-brown, white at the base, but 

 that colour not apparent until the coverts are raised. On the 

 lower parts the light greyish-brown feathers have a brownish- 

 red medial and terminal mark, which beyond the middle of 

 the breast becomes moi'e diffuse, and blended. The lower 

 wing-coverts are dark brown. The wdiite on the primaries 

 forms a large patch, similar to that on the under surface of 

 the wing in Buzzards and Eagles. 



Length to end of tail 24 inches ; extent of wings 55 ; 

 wing from flexure 16^ ; tail 7;^ ; bill along the ridge 2^, 

 along the edge of lower mandible 2^, its height at the base 

 •fl, at the knob -^ ; tarsus 2^ ; hind toe -yj, its claw -f^ ; 

 second toe l-j^^, its claw -f-^ ; third toe 2^, its claw -j^; 

 fourth toe 2^^, its claw -p^. 



Habits. — From the hook-pointed strong bill, and curved 

 acuminate claws of this bird, together with its compact form, 

 one might suppose that its obvious analogy in structure to 

 the rapacious birds would lead to a corresponding similarity 

 of habits. The inference proves, in fact, to be in a great 

 measure correct, for the Skua has much of the aquiline cha- 

 racter, although it is not known to pounce on its prey and 

 carry it off in its claAvs. On the other hand, it bears a great 

 resemblance to the Gulls propeily so called, both in form and 



voj,. v. 2 I 



