THE BIRDS 219 



chick (Podilymlus podiceps), for example, found abun- 

 dantly on the larger lakes and streams throughout the 

 United States, captures its food, sleeps, and breeds with- 

 out leaving the water. The loons living in the same situa- 

 tions as the dabchick are also remarkable swimmers and 

 divers. Of the three species found in this country, the 

 common loon or diver (Gavia imber] attains a length of 

 three feet, and is otherwise distinguished by its black 

 plumage, mottled and barred with white, which is also the 

 color of the under parts. The auks, murres, and puffins 

 are marine, and, like their inland relatives, are expert 

 swimmers and divers, strong fliers, and spend much of their 

 time on the open sea. During the breeding-season they 

 assemble in vast numbers on rugged cliffs along the shore, 

 and lay their eggs on the bare rock or in rudely constructed 

 nests. 



204. The gulls, terns, petrels, and albatrosses (Longi- 

 pennes). The birds belonging to this group are among the 

 most abundant along the seacoast, and several species make 

 their way inland, where they often breed. All are char- 

 acterized by long, pointed wings and pigeon or swallow-like 

 bodies, which are carried horizontally as the bird waddles 

 along when ashore. Many are excellent swimmers and 

 powerful fliers, especially the petrels and albatrosses, which 

 sometimes travel hundreds of miles at a single flight. 



The gulls are abundantly represented along our coasts, 

 where they frequently associate in companies, usually rest- 

 ing lightly on the surface of the water, or wheeling lazily 

 through the air on the lookout for food. The terns are 

 of lighter build than the gulls and are more coastwise in 

 their habits, and are further distinguished by plunging like 

 a kingfisher for the fishes on which they live. Both, the 

 gulls and terns breed in colonies, every available spot over 

 acres of territory being occupied by their nests, which are 

 usually built of grass and weeds placed on the ground. 



The petrels and albatrosses are at home on the high 



