l66 THE DUCK-BILLED PLATYPUS. 



which had been kept in spirits, and was tolerably 

 perfect. He discovered that although the beak, 

 when cursorily examined, had so great a resem- 

 blance to that of the Duck, as to induce a belief 

 that it was calculated for exac::ly the same purposes ; 

 yet when all its parts were carefully reviewed, he 

 found that it differed in a variety of circumstances. 

 This, it appears, is not the animal's mouth ; but is 

 merely a projecture beyond, and added to it. 



The cavity of the mouth is similar to that of 

 other quadrupeds, and has two grinders on each 

 side, both in the upper and under jaw : but instead 

 of front-teeth, the nasal and palate bones are con- 

 tinued forward, lengthening the anterior nostrils, 

 and forming the upper part of tlie beak ; and the 

 two portions of the lower jaw, instead of terminat- 

 ing, as ill other quadrupeds, are also continued for- 

 wards, forming the under portion of the beak. This 

 structure diffeis materially from the bills of all birds: 

 since in the feathered tribe the cavities of the nos- 

 trils do not extend beyond the root of the bill ; and 

 in the lower portions, which correspond v.'ith the 

 under jaw of quadrupeds, the edges are hard, to 

 answer the purpose of teeth, and in tiie middle there 

 is an hollow space to receive the tongue ; but in the 

 Plat}^pus the two thin plates of bone are in the 

 centre, and the parts that surround them are com- 

 posed of skin and membrane, in which, probably, 

 a muscular structure is included. 



The teeth have no f^mgs that sink into the jaw, as 

 in most other quadrupeds, but are embedded in the 

 gums. — The tongue is scarcely half an inch long, 



