THE LONG-TAILED OR BUFF ON' S SKUA 349 



forms or races of this bird have been observed 

 one dark, the other light. Colonel Irby states 

 that the name of Arctic as applied to this bird is 

 a misnomer, since it breeds and migrates further 

 South than any of the other Northern skuas. 

 Including the centre tail-feathers, its length is 

 twenty inches. The dark variety is of a sooty- 

 brown colour in plumage. The light, in which 

 the centre tail - feathers are but three inches 

 longer than the others, has the crown black ; 

 the upper parts brownish-gray ; the sides of the 

 neck white ; the under parts white ; the legs 

 slate-gray. 



The plumage of the long-tailed or Buffon's 

 skua is the same as that of the light variety of 

 Richardson's skua. Colonel Irby remarks that 

 there is this difference between the two birds, 

 apart from that in their measurements, viz., that 

 ' it is said that the nostrils of Buffon's skua are 

 nearer the frontal feathers than the tip of the 

 bill ; whereas in Richardson's skua the contrary 

 is the case. In length, inclusive of the tail- 

 feathers, the long-tailed skua measures twenty- 

 three inches. It is said to be comparatively 

 common on the East coast of England. Its 

 visitation occurs from the autumn to the spring.' 



The following constitute the list of .the British 

 auks (the Alcidae) : 



1. The great auk (extinct). 



2. The razorbill. 



3. The common guillemot. 



