346 ZOOLOGY. 



characterized by their legs, of moderate length, terminated by 

 large webbed feet. These serving the purpose of oars, are 

 formed by the toes being united to each other by an inter- 

 digifcal membrane of the common integument ; the legs are 

 placed far back, which is favourable for swimming, but ill 

 adapted for walking : as examples of this group we may men- 

 tion the auks (Fig. 294), the penguins, which have the wings 



Fig. 341. The Trumpeter Bird.* 



so short that they cannot fly ; the petrels, the albatrosses, 

 the gulls, and the terns (Fig. 343), which have, on the 

 contrary, long wings, and a powerful flight ; the pelicans 

 (Fig. 311), the frigate birds, and the boobies, which are 

 as well organized for flight as the preceding, and the first still 

 more completely webbed ; finally, the swans, the geese, and 

 the ducks (Fig. 300), whose bills are covered with a soft skin 

 instead of a horny envelope. 



* Attempts are now being made to acclimatize this South American bird 

 in the South of France. 



