JAAVS OF BIRDS. 131 



Toucan and the Parrakeet, appears, in like 

 manner, to be the detention of substances intro- 

 duced into the mouth. 



The beak of the Hcematopus, or Oyster-catcher, 

 has a wedge shape, and acts like an oyster- 

 knife for opening bivalve shells. 



In the LiOxia curvirostra, or Cross-bill, the 

 upper and lower mandibles cross each other 

 when the mouth is closed, a structure which 

 enables this bird to tear open the cones of the 

 pine and fir, and pick out the seeds, by insi- 

 nuating the bill between the scales. It can split 

 cherry stones with the utmost ease, and in a 

 very short time, by means of this peculiarly 

 shaped bill.* 



Birds which dive for the purpose of catching 

 fish have often a bill of considerable length, 

 which enables them to secure their prey, and 

 change its position till it is adapted for swal- 

 lowing. 



The Rliyiichops, or black Skimmer, has a very 

 singularly formed beak ; it is very slender, but 

 the lower mandible very much exceeds in length 

 the upper one, so that while skimming the 

 waves in its flight, it cuts the Avater like a 

 plough-share, catching the prey which is on the 

 surface of the sea. 



The Woodpecker is furnished with a singular 



"" See a paper on the mechanism of the bill of this bird, by 

 Mr. Yarrell, in the Zooloo^ical Journal, iv. 459. 



