Heads and Necks 



275 



We must pass by all the strange ornaments of horn 

 upon the heads of birds, such as the scarlet plate of the 

 gallinules, the immense recurved casques of the hornbills, 

 the use of which is as yet unknown, unless it be ])urel3' 

 ornamental. But the impressive helmets of the cassowaries, 



Fig. 218.— Head of Wild Turkey. 



Fig. 228, demand especial notice in this volume, as being very 

 useful adaptations to life in a dense forest. These great 

 running birds are the only members of their Sub-class 

 which inhabit thickly forested regions, and in speeding 

 with great leaps and bounds through the undergrowth, the 

 tall, smooth helmet of horn protects the head of the bird 



