178 
LARID.E 
tlie foregoing species; but it requires still great attention to 
clistinguisli them in all states. 
We will endeavour to explain the most prominent 
marks of distinction by which the present species may be 
known. 
The adult Richardson’s Skua measures seventeen inches 
from the end of the beak to the tips of the tail-feathers, 
next to the two elongated middle feathers, or twenty inches 
to the tips of the longest feathers in the tail. The 
grey plumage on the breast entirely encircles the front, 
and the belly is white ; the legs are black, and of a uni¬ 
form colour. 
The arctic skua measures only thirteen inches and a 
half to the same part, or twenty-two to the extremity of 
the longest feathers in the tail. The dusky grey colour 
on the breast is confined to the sides of the breast, leaving 
the front or middle part white, with a yellow tinge; the 
legs are blue on the front and sides of the tarsi, and black 
at the back and lower joint, as well as the toes and their 
membranes. 
Many instances of the boldness and hardy nature of this 
species have been recorded by naturalists ; namely, that it 
will suffer itself to be fired at several times before it makes 
any attempt to fly off; and if sticks or stones are thrown at 
it when on the ground, it will run up and bite or peck at 
them. 
Sociability is not one of its virtues, which the frequent 
quarrels and fights that take place among individuals of this 
species prove, when the birds scratch and bite each other until 
they tumble together to the ground. 
The food of this species consists in the same disgusting- 
matter as that of the preceding; but land insects, small 
