ARCTIC ZOOLOGY. 143 



sixteen inches long. This bird, so pleasing to the observer, 

 is sure to torture him with its perpetual and disagreeable 

 screaming. 



Larus Canus (common grey gull) is not frequently seen. 

 The same may be observed of the L. cataractes or skua 

 gull, and also of the L. fuscus, or herring gull. 



Larus Tridactylus (kittiwake or tarrock), is very nume- 

 rous in Davis's Strait. The trivial name is derived from 

 its cry, which is a shrill scream, somewhat resembUng the 

 word kittiwake. It may be known from the young ivory 

 gull, by the bill being yellowish, and the mouth of a 

 saffron colour within. 



Larus Parysiticus (arctic gull, or boatswain). — This bird 

 is very rapacious, pursuing the weaker gulls until fear from 

 continued pursuit causes them to discharge what they have 

 eaten, which it dexterously catches and devours before it 

 can reach the water. The two middle tail feathers are 

 very long, but the females are said to be destitute of this 

 mark : many of the species being seen together, a few 

 only have those remarkable feathers. The boatswain is 

 very fond of tlying round the pennants of the ships, but 

 no cause can be assigned for this singular habit. Its colour 

 is generally brown. 



Stuna Hirundo (the greater tern). — This beautiful bird is 

 seen in great numbers, sometimes thousands together, rest- 

 ing on an ice berg, and, when on wing, exhibits a graceful 



