272 BEACH GRASS 



the dance. Incidentally, and perhaps accident- 

 ally at first, a loud booming sound is produced by 

 the rush of air through the wing feathers. This 

 instrumental music is now the important feature, 

 although the dance is by no means a negligible 

 one. The raven turns a rolling-over somersault 

 in the air, and the marsh hawk plunges from a 

 great height, loops the loop or turns a sidewise 

 somersault. The chat with dangling legs dances 

 crazily about in the air, and the kingbird executes 

 a series of zig-zag and erratic flights, emitting at 

 the same time a harsh double scream. This is 

 a true courtship flight song but it is neither grace- 

 ful to our eyes or pleasing to our ears. The 

 taste of the kingbird in these matters appears to 

 us to be poor. 



The impossibility of treating in turn only one 

 of the primary divisions — display, dance and 

 song is well shown by these examples. The case 

 of the courtship of the heath hen is still more 

 difficult for all three factors are inextricably 

 mingled. I have already alluded to the display 

 of neck-sacks of this bird, orange in color and 

 shape, a very striking and beautiful feature, but 



