THE DIGESTIVE SYSTEM 



41 



No modern bird possesses teeth ; but very 

 rudimentary enamel organs have been described 

 in the embryos of some birds. 



Fig. 10.— Roof of Mouth 

 and Pharynx. 



A, hard palate ; B, opening 

 from nose ; C, common opening 

 of the Eustachian tubes. 



Fig. 11.— Floor of Mouth and 

 Pharynx. 



A, tongue ; B, opening into larynx ; C, 

 hyoid bone ; D, oesophagus. 



The tongue (Fig. 11) is narrow and pointed 

 in conformity with the shape of the beak. The 

 epithehum is thick and horny, especially to- 

 wards the tip of the tongue ; and the posterior 



