44 SECOND FLOOR, SOUTH CENTRAL WING 



In the middle of the hall are various cases showing characteristic scenes 

 of bird life. A group of ptarmigan in seasonal plumage is 

 at the entrance. Unlike most birds the ptarmigan has three 

 distinct molts a year: From the pure white of winter it passes in the 

 spring into the dark gray-brown plumage of summer. It again sheds 

 its feathers in the fall, acquiring a plumage of lighter brown which har- 

 monizes more nearly with its surroundings. Then later it passes into its 

 Great Auk wmt er plumage of white. Beyond the ptarmigan group is 

 the great auk case and the Labrador duck group; both of 

 Labrador these birds are now extinct, and there are only four mounted 

 specimens of the former in this country. 

 In a case near the center of the hall is an exhibit illustrating the differ- 

 ences in structure of the beaks and claws of birds, and some of the habits 

 of various species of North American woodpeckers. 



At the north end of the hall is a nearly complete collection of the birds 



of paradise of the world, presented by Mrs. Frank K. Sturgis. Birds of 



paradise are confined exclusively to New Guinea and a few 



Paradise adjacent islands. This collection illustrates the remarkable 



modifications that the feathers of a single group of birds 



may undergo in nature. 



Finback Suspended from the ceiling of this hall is the skeleton of 



Whale a finback whale, sixty -two feet in length. 



CORRIDOR OF CENTRAL PAVILION 



Recent Fishes 



The doorway at the north end of the hall of the birds of the world 

 leading to the rear of the bird of paradise case opens into the gallery of 

 the Auditorium and to the corridor devoted to the general collection of 

 recent fishes. This hall contains representatives of the marine and 

 fresh-water fishes of the world. The exhibit includes typical examples of 

 the various groups of vertebrates popularly comprised in the term 

 "fishes" and is arranged to show first the most primitive fishes, the sharks, 

 then successively various groups leading up to the teleosts or bony fishes, 

 which were the last to appear in the course of evolution. These groups are 

 as follows: lampreys and hagfishes, eel-like creatures with round sucking 

 mouths and no jaws, hence not realty fishes in the strict sense of the word; 

 sharks and rays, the most primitive, that is the most ancient type of fishes ; 

 chimseroids or rat-fishes, a group of highly modified sharks living mostly 

 in the deep sea; lungfishes, an ancient group represented at the present 

 time by three kinds or genera, living respectively in the rivers of Australia, 



