WILD DUCK. 277 



cavity before it becomes united with the air from the other 

 lobe in the tube common to both. A compound tone of 

 voice is thus produced by which wild-fowl shooters can 

 distinguish males from females, of the same species, in the 

 darkest night, whenever the birds utter their note, and 

 this they frequently do, apparently for the purpose of 

 keeping together. Gilbert White of Selborne, with his 

 usual discrimination, says, in his forty-third letter to 

 Daines Barrington, which is devoted to the consideration 

 of the notes and language of birds, " among Ducks the 

 sexual distinction of voice is remarkable ; for, while the 

 quack of the female is loud and sonorous, the voice of 

 the Drake is inward, and harsh, and feeble, and scarce 

 discernible." 



The resemblance to the reed or other mouth -piece, and 

 the edge opposed to its inner orifice, to produce vibration, 

 in some musical wind instruments, will be obvious. 



