136 THE VITAL FUNCTIONS', 



In the animals belonging to the genus FeliSf 

 each of the papillae of the tongue is armed with 

 a horny sheath terminating in a sharp point, 

 which is directed backwards, so as to detain the 

 food and prevent its escape. These prickles are 

 of great size and strength in the larger beasts of 

 prey, as the Lion and the Tiger ; they are met 

 with also in the Opossum, and in many species 

 of bats, more especially those belonging to the 

 genus Pteropus : all these horny productions 

 have been regarded as analogous to the lingual 

 teeth of fishes, already noticed. 



The mouth of the Ornithorhyncus has a fonn 

 of construction intermediate between that of 

 quadnipeds and birds ; being furnished, like 

 the former, with grinding teeth at the posterior 

 part of both the upper and lower jaws, but 

 they are of a horny substance ; and the mouth 

 is terminated in front by a homy bill, greatly 

 resembling that of the duck, or the spoon- 

 bill. 



The Whale is furnished with a singular appa- 

 ratus designed for filtration on a large scale. 

 The palate has the form of a concave dome, and 

 from its sides there descends vertically into the 

 mouth, a multitude of thin plates set parallel to 

 each other, with one of their edges directed 

 towards the circumference, and the other towards 

 the middle of the palate. These plates are known 

 by the name of whalebone^ and iheir general form 



