GULLS. 313 



Ocean, yet several specimens have been obtained 

 in this country. 



FAMILY V. LARID^E. 



(Gulls.) 



Through the Skuas, which have somewhat of 

 the form of beak we have last described, the 

 passage from the Petrels to the Gulls is easy and 

 obvious. These are, for the most part, birds of 

 large size, in which the swimming and diving 

 structure recedes, and the most prominent actions 

 are those of flying and walking. " The whole of 

 the Family," observes Mr. Vigors, who includes 

 in it the Petrels, " is distinctly characterized by 

 the strength and expansiveness of their wings, 

 with the aid of which they traverse immeasurable 

 tracts of the ocean in search of their food, and 

 support their flight at considerable distances from 

 land, seldom having recourse to their powers of 

 swimming. We may thus discern the gradual 

 succession by which the characters peculiar to the 

 Order descend from the typical groups that swim 

 and dive well and frequently, but make little use 

 of their wings for flight, to the present groups, 

 which are accustomed to fly much, but seldom 

 employ their powers of swimming, and never 

 dive."* One can scarcely look at a Gull, without 

 being strongly reminded of the Wading-birds, 

 and particularly the Plovers, to which in general 

 form, in attitude, in the long and slender tarsus, 

 with the hind-toe minute and set high up (as in 

 ) in the naked space above the heel, and 



* Linn. Trans, vol. xv. 



