ON THE TRACHEA OF THE GALLINZE. 493 
Fig. 19. 
Front view. 
Tetrao tetrix, g- 
varying in the least, as far as I can detect, from their arrangement in 
the female. 
Tetrao urogallus (a male, not quite full-sized, and without any 
trace of the cervical loop developed) differs from the female of T. tetriz 
Fig. 20. Fig. 21. 
Front view. 
Tetrao urogallus. 
