382 DIGESTIVE APPARATUS OF BIRDS. 



and to grind down its contents. This organ is most muscular 

 in granivorous Birds ; the thickness of its fleshy sides is con- 

 siderable ; and its inner surface is covered with a sort of almost 



CEsophagus. 



p Crop. 



Ventriculus 

 succenturiatus 



Gizzard 1^--- Liver. 



Gall-bladder. 

 r- Bile-ducts. 



Fio. 201. DIGESTIVE APPARATUS OK FOWL. 



cartilaginous epithelium. Its strength is immense ; in the Ostrich 

 for instance, the hardest bodies have been ground down by its 

 contractions ; and it evidently takes the place of an apparatus 

 for mastication. 



345. The Intestine, which forms the continuation of this 



