»20 PALMIPEDES. 



FAMILY III. 

 A L( • I D.E. The A uks. 



Gkn. Charac— Bill more or less long-, generally compressed on the sides, and 

 the culmen usually curved to the tip, which is sometimes hooked ; the wings 

 generally short, and more or less imperfectly formed ; the tail short and gra- 

 duated; the tarsi usually short and compressed; the toes entirely webbed, 

 with the hind toe small or wanting. 



The birds belonging to this family are distin- 

 guished by having only three palmated toes, and 

 where a fourth or hind toe does exist, it is very small, 

 without any web, and inclined forwards. The Alcidse 

 are distributed in most parts of the world, but most 

 numerously in high northern and southern latitudes. 

 They are found upon the barren rocky shores of the 

 Arctic and Antarctic lands and islands, often in 

 flocks coiisisting of vast numbers of individuals. 

 They pass the greater part of their time in the sea, 

 whence they obtain an abundant supply of food, 

 which they procure by diving. In these birds, 

 shortness of wing, and consequent deficiency in 

 their powers of flight, are carried to the greatest 

 extreme, the wings of the Penguins and other allied 

 genera being so small and imperfectly developed as 

 to be totally unfit for flying, and adapted to act 

 merely as fins to aid their progress beneath the 

 water. As in the Colymbidge, the legs of these 

 birds are placed far backwards, but at scarcely so 

 great an angle with the body. In consequence of 

 this, they are enabled to sit in an upright attitude, 

 resting equally on the foot and on the whole length 

 of the tarsus. They are all birds of the ocean, never 

 resorting to fresh water, as the Divers do. Many 

 of the species that are able to fly, nestle on the rocks 

 and precipices, where they lay a single egg of 

 conical form, a shape which prevents it from rolling 

 away, or moving except within a circle of the 

 diameter of its own length, on the bare ledge of 



