l62 



GULL GROUP 



Kittiwake '"^^ indicated by its scientific name, the gull 



(Rissa commonly known as the kittiwake, which is an 



tridaetvla) indigenous British species, and our last repre- 

 sentative of the gulls, is sharply distinguished 

 from all its kindred by the absence of the hind-toe. Occasionally, 

 however, that digit is represented by a small rudiment ; and as this 

 rudiment is said to be more commonly seen in kittiwakes from the 

 North Pacific, such birds have been regarded as indicating a separate 

 species, but this view is now generally rejected. On the other hand, 

 a kittiwake with vermilion feet and grey under wing-coverts, inhabiting 

 Bering Sea and its neighbourhood, is undoubtedly entitled to specific 



separation, and is known as R/ssa brcvirostris. In addition to the 

 lack of the hind-toe, these species present two other characteristics 

 in common, namely, the shortness of the shank or lower segment of 

 the leg, which is inferior in length to the middle -toe and its claw, 

 and the tendency towards forking in the tail. In some ornithological 

 works, it should be mentioned, the kittiwake is styled Rissa rissa, 

 instead of by the title here given. 



The kittiwake, which is a circumpolar species, presents a remark- 

 able difference as regards its distribution from species like Ross's and 

 the ivory gull, whose breeding-range is confined to the frozen north. 

 The kittiwake, on the other hand, although it has been met with 

 beyond Spitsbergen so far as man has penetrated, while in Smith 

 Sound it is known to range some distance beyond the 8ist degree of 



