116 EGGS OF BRITISH BIRDS. 



THE POMATOEHINE SKUA. 

 ( Stercorarius pomatorhinus.) 



Plate 37, Fig. 6. 



This Skua is a more or less common winter visitor to the British 

 Islands, occurring more abundantly on the east than on the west 

 side. It is a circumpolar species, breeding beyond the Arctic circle 

 on the shores and tundras of both hemispheres. Middendorff, who 

 found this species breeding near the Taimur Lake in lat. 74° N., 

 obtained eggs on the 19th of July. 



No nest was made beyond a depression in the moss on the 

 tundra. 



The number of eggs seems to be never more than two, but on 

 the Yalmal Peninsula Finsch never found more than one nestling 

 with the parents. The eggs vary in ground-colour from dark 

 russet-olive to pale olive ; the surface-spots are often blurred, 

 and are generally most abundant round the large end, where 

 they are sometimes confluent, and are very irregular in shape, 

 varying in size from that of a large pea downwards, and are 

 of a dull reddish-brown in colour ; the underlying spots are 

 dull greyish -brown. They vary in length from 2'4 to 2'25 

 inches, and in breadth from 17 to 16 inch. They are indis- 

 tinguishable from certain varieties of the eggs of Kichardson's 

 Skua and the Common Gull. 



EI CHARD SON'S SKUA. 



( Stercorarius richardsoni.) * 



-Plate 37, Figs. 1, 2. 

 Richardson's Skua is by far the most common species of the 

 genus which visits the British Islands, but its best known 

 breeding-places are on the Outer Hebrides, principally North and 

 South Uist, and on the Orkney and Shetland Islands. Booth 

 found it nesting on the moors in Caithness, and it is said to breed 

 regularly in Sutherlandshire. It is a circumpolar bird, breed- 

 ing in the Arctic and Sub-arctic regions of both hemispheres, 

 including the Faroe Islands, Iceland, Spitsbergen, and Novaya 

 Zemlya. 



* Stercorarius crepidatus — Saunders, Manual, p. 675. 



