34 



FORM AND HABIT: THE BILL. 



tEat Of the female is long and curved. The birds feed 

 on larvae, .vdnch they find in dead wood. The male 

 hammers and chisels away the wood very much as Wood- 

 peckers do, while the female uses her bill as a probe 

 We have, therefore, the singular case of two forms of 

 the bill arising in the same species as a result of or caue- 

 ing a corresponding difference in habit. 



