60 



White-bellied Swift (alpine) {Cyfselus melba). 



Roller {Coracias garrulus). 



Spotted Eagle {Aquila clanga). 



Red-footed Falcon {Tinnunculus vespertinus) 



Purple Heron {Ardea purpurea). 



Little Bittern {Ardea minuta). 



Night Heron {Nijcticorax griseus). 



American Bittern {Butaurus lentiginosus). 



Spoonbill {Platalea leucorodia). 



Whooper Swan [Cygnus musicus). 



White-eyed Duck {Nyroca ferruginea). 



Velvet Scoter {CEdemia fusca). 



Surf Scoter {CEdemia perspicillata). 



Baillon's Crake {Porzana hailloni). 



Little Crake {Porzana parva). 



Crane {Grus communis). 



Little Bustard {Otis tetrax). 



Sociable Plover {Vanellus gregarius). 



Buff -breasted Sandpiper {Tringites rufescens) 



Red-breasted Snipe {MacrorJiampus griseus). 



Roseate Tern {Sterna dougalli). 



Gull-billed Tern {Sterna anglica). 



White-faced Petrel {Porcellaria marina). 



Sabine's Gull {Xema sabinii). 



Iceland Gull {Lartis leucopterus). 



Case 2 29. 



The specimens in this case are designed to show the remarkable 

 changes in the plumage of many birds, according to age and season. 

 Many gulls, for example, difier so much from year to year in the first 

 four or five years of life that birds of the same species during this 

 period are often mistaken for different species. Some species of birds 

 have a summer or breeding plumage, which is quite different to the 

 winter plumage, and males are often very different from females. 



RED-THROATED DIVER {Colymhus septentrionalis). 

 Four specimens to illustrate the stages in the change of plumage of 

 this species from the chick to the adult. The complete breeding 

 plumage of this species may be seen in the group, Case 217. 



BLACK GUILLEMOT {Uria grylle). 



Ten specimens showing the stages in the change of plumage 

 from the chick to the adult summer plumage, and from this to the 

 winter plumage. The first plumage of the young Black Guillemot, 



