TASTE OF INSECTIVOROUS BIRDS, 



181 



by bristles (yibrissce) at the root of the bill, not un- 

 like the whiskers of a cat, and probably intended to 

 aid them in capturing their prey. These bristles are 

 larger in the night-jars than in most other birds, but 

 are very distinct in most of our small birds, such as 

 the nightingale, the redbreast, the flusher (Lanius 

 collurio), the beautiful bird called the roller (Coracias 

 garruld), which on rare occasions pays us a transitory 

 visit, and the fly-catchers (Muscicapida), 



Head of the Roller, showing the vibrissae. 



The latter differ considerably in their mode of 

 hunting from several other species which take insects 

 chiefly on the wing. Instead of keeping up a con- 

 tinuous flight like the swallow or the bat, the fly- 

 catcher chooses a station where he can take good ob- 

 servation of all the insects which may venture within 

 his boundaries generally the dead leafless branch of 

 a tree, or the top of a gate-post ; whence, in Kent, 

 the common fly-catcher (Muscicapa gruola) is ex- 

 pressively called the post-bird. "This fly-catcher," 

 says Mr. Knapp, "delights in eminences. The naked 

 spray of a tree, or projecting stone in a building, or 



