68 



CORVID^E. 



which has made equal proficiency ; for, living within the 

 vicinity of a guard-house, it has more than once turned 

 out the guard, who thought they were called by the sen- 

 tinel on duty."" Fauna Boreali- Americana. Swainson 

 and Richardson, Part II. page 290, note. 



The advantageous size of the organ of voice in the 

 Raven, and its perfect similarity to those of all our song- 

 birds, induced me to select it in illustration of this subject, 

 although in the quality of its tone there is no resemblance ; 

 but it should be borne in mind, that this bird possesses 

 the power of imitating the most difficult of all sounds, 

 the human voice, for which numerous muscles appear to 

 be necessary. The illustrations here given, are exactly of 

 the same size as the parts themselves will be found in the 



