632 AVES [CH. 



aquatic, swimming and diving Birds with flattened legs nidifugous 

 young and schizognathous palate. The Diver (Colymbus) is well known 

 on our northern coasts ; it is called the Loon in N. America. 

 Another form common to England and N. America is the Grebe 

 (Podiceps\ in which the toes are fringed with separate webs not united 

 into a common web. The Procellarii formes, which include the 

 Petrel (Procellarius), and the Albatross (Diomedea), are also swim- 

 ming and diving Birds, but they differ in being nidicplous and in 

 retaining the curious primitive character in having the covering of 

 the bill made up of several plates, recalling the scales of Reptiles, 

 whereas in most Birds it consists of a single horny sheath, which no 

 doubt has been produced by the fusion of several Such scales. The 

 Penguins (Sphenisciformes) are known to all frequenters of the 

 London Zoological Gardens by the upright gait and curious paddle- 

 like wings in which the feathers have degenerated into scales. The 

 toes are webbed, for these also are swimming and diving Birds which 

 use the wings as well as the feet to swim with. The palate is schizo- 

 gnathous. All the Penguins belong to the Southern Hemisphere. 



More familiar are the Duck-like Birds (Anseriformes) distin- 

 guished by the series of transverse horny ridges on the palate, 

 extending to the edges of the bill and enabling these Birds to 

 either crop water plants or to hold struggling aquatic prey, like 

 frogs. The toes are webbed and the palate desmognathous. The 

 Anseriformes include all our Swans, Ducks and Geese. 



Equally well characterised are the Birds of Prey or Falcon-like 

 Birds (Falconiformes), distinguished by their powerful arched beak 

 with cutting edges, the desmognathous palate and above all by the 

 cruel curved talons on their toes. These claws are the real weapons 

 of attack the beak is only used to tear off the flesh of the prey 

 when it has been killed. The Golden Eagle, our largest Bird of 

 Prey, has been known to kill a full-sized cat with a single blow 

 of its claws. 



The Ciconii formes, or Stork-like Birds, are a more diversified 

 group. They have a desmognathous palate and usually a long 

 spear-like beak, with which they impale the fish on which they 

 feed. This group includes not only the Storks and Herons in 

 which the legs are long and the toes free, but the so-called 

 Steganopoda (Pelicans and Gannets), in which all four toes are 

 included in one web and the legs are short. 



The Gruiformes, or Crane-like birds, including the Cranes and 

 Rails are often confounded with some of the Ciconiiformes, as many 



