84 



Monotjraph of the Cranes. 



depending on the age of the bird examined. In adult birds the entire 

 length of the trachea is twenty-seven inches, there being about eight or 

 nine inches in the keel, as shown in the diagram. 



SiEENUM AND Teachea OF THE SANDHILL Ckane. Gtus Canadensis. 

 For the voice of this species I will quote from the admirable account 

 given by Dr Elliot Coues in his " Birds of the North-West," in which we 

 are informed that : 



When proceediug from one favourite resort to another, or when migrating, the flight 

 is high, and not unfrequently their approach is heralded, before they are in sight, 

 by their incessant, whooping clamour. . . . We found them always exceedingly shy and 

 difficult of approach, but not unfrequently the files of their tall forms stretching above 

 the prairie grass, or their discordant and far-sounding screams, suggested the presence 

 of the human inhabitants of the region, whose territory was now, for the fir.st time, 

 invaded by the white man. . . . Tiet the least sound or movement betray an unwelcome 

 visitor, the crane spreads his ample wings and springs heavily into the air, croaking 

 dismally in warning to all his kind within the far-reaching sound of his voice. 



In the common crane {G. iwnmunis) the convolutions of the ti-achea, 

 which are figured in Yarrell's " British Birds," closely resemble those of 

 the saras crane, there being four folds, but the hinder bend passes to the 

 extremity of the keel. The far-resounding voice of this bird is well known. 



Steenum and Teachea or Whooping Ceane. Grus americana. 

 The most extreme development of the trachea in the cranes is to be seen 

 in that one which is frequently termed the whooping crane of America 

 {G. americana). It has a windpipe between four and five feet long, of which 

 no less than tsventy-eight inches are coiled up in the keel of the breast-bone, 

 as hliowu in the foregoing diagram. 



