478 LESTRIS. SKUA. 



with dense, rugous epithelium ; intestine rather short and 

 wide, cu3ea rather long. 



Eyes rather small, eyelids feathered. Feet of moderate 

 length, rather strong ; tihia bare below ; tarsus moderately 

 compressed, with anterior decurved scutella, the lateral and 

 posterior scales convex ; hind toe elevated, very small, with a 

 rather large, arcuate, acute claw ; anteiior toes rather long ; 

 interdigital membranes entire; claws much curved, com- 

 pressed, acute. 



Plumage full, close, firm, on the back and wings compact. 

 Wings very long, rather broad, pointed. Tail of twelve fea- 

 thers, of which the two middle are elongated. 



These birds are especially remarkable for their habit of 

 pursuing and harassing Gulls and Terns, to cause them to 

 disgorge a portion of their food, on which they seize as it falls 

 from them. If they ever fish for themselves it must be sel- 

 dom, as they who have had opportunities of watching or oc- 

 casionally observing, have not recorded instances, although 

 some allege that they feed on the carcases of whales and other 

 animals, especially fishes. Their flight resembles that of the 

 Gulls, but is more bounding, and at the same time capable of 

 being urged to much greater speed. The curvature of their 

 claws must be intended for prehension, though they certainly 

 do not seize upon the birds W'hich they pursue. 



There is difficulty in determining the correct generic 

 appellation of these birds. I think, however, that as no ac- 

 curate ideas of either generic or specific nomenclature were 

 entertained before the time of Linnaeus, we ought to adopt 

 Illiger's name Lestris. " Skua " has been used by Mr. Selby 

 as generic, and adopted by Mr. Thompson. " The Skua," or 

 " Skua Gull," however, is properly a specific name, analogous 

 to " The Knot " or " The Dunlin ; " and as Lestris means a 

 robber, and a sea-robber is a " pirate," I should prefer the 

 latter word. 



