CLASS AVES 609 



and nest in colonies. The black skimmer, Rynchops nigra, is 

 found along our Atlantic coast. It flies along the surface of the 

 water with its lower mandible immersed, and literally skims small 

 aquatic animals from the top. 



The ALCID.E are the puffins, auklets, murrelets, murres, 

 guillemots, and true auks. They spend a large part of their 

 existence at sea. Most of them are strong fliers, and excellent 

 swimmers and divers, but very awkward on land. They feed on 

 fish, crustaceans, and other small marine animals, and nest in 

 colonies, usually on rocky shores. The puffins, or sea-parrots, 

 are grotesque-looking birds 

 with enormous beaks that are 

 grooved and brightly colored. 

 The murres possess bills which 

 are narrow and without 

 grooves. 



The true auks are North 

 American birds represented 

 by three species. The great 

 auk, or garefowl, Plautus im- 

 pennis (Fig. 498), became ex- 

 tinct in 1844, when the last 



One appears to have been FlG 49- "Great auk, Plautusimpennis. 



(From Evans, after Hancock.) 



killed. They were destroyed 



for their feathers, and their eggs were used as food. " All that 

 remains to-day of the Great Auk are about seventy skins, sixty- 

 five eggs, and some twenty-five more or less perfect but com- 

 posite skeletons, that is, skeletons made up from the bones of 

 many different individuals." (Knowlton.) 



The COLUMBID^E are the pigeons or doves (Fig. 470) of which 

 twelve of the three hundred known species occur in North 

 America. The passenger-pigeon, Ectopistes migratorius, is an- 

 other bird that is practically extinct, although flocks were seen 

 a century ago that contained over two billion birds. The mourn- 

 ing-dove, Zenaidura macroura, is common and often mistaken 



