t28 THE COURTSHII* OF ANIMALS 



running to the lungs. That we have here an indubitable 

 musical instrument there can be no question, for its 

 possessor is enabled thereby to utter loud, trumpet-like, 

 if harsh, sounds. Here again only the males are so 

 provided. 



The profound interest of this really extraordinary 

 association of unrelated structures has never attracted 

 the attention it deserves. Originally, no doubt, one would 

 have met with nothing more than a loop of the windpipe 

 impinging against the anterior border of a normal, blade- 

 like keel : later there would have been formed a broad 

 shallow surface on the keel at the point of contact 

 with the loop, and gradually the depression must have 

 deepened till the bony chamber came into being. By 

 what nexus of sympathy were these reciprocal responses 

 made ? 



Another very singular type of looped windpipe is that 

 wherein the trachea forms a series of coils between the 

 body and the skin. It is surely somewhat surprising 

 to find that precisely similar coils are met with in widely 

 different groups of birds. Among the Passeres they occur 

 in the Manucode : among the Plovers in the Painted 

 Snipe (Rhynchea rostratula) : among the game-birds in 

 some of the Curassows, and among the Anatidae in the 

 aberrant Australian Black-and- White Goose (Anseranas). 



Very little is really known of the part played by these 

 musical instruments of the Anatidae, nor, for the matter 

 of that, of most of the " musicians " among birds. Of 

 some of the game-birds more has been gleaned, and among 

 these surely the most interesting is the love-song or " lek " 

 of the Capercaillie. With the advent of April the cock, 

 just before dawn, repairs to some favourite tree — used 

 year after year — and there performs a most astonishing 



