604 



THE DIGESTIVE SYSTEM 



STOMODAEUM 



FOREGUT 

 STOMODAEUM 



ANTERIOR 

 MTESTINAL 

 PORTAL 



;^^PROCTODAEUM 



B 



50 - 56 HOURS 



SMALL INTESTINE 

 ARGE INTESTINE 



GALL BLADDER 



RIGHT LIVER LOBE 



Fig. 281. Morphogenesis of the gut structures in the chick, Callus (domesticus) gallus. 



and the copula protuberance which forms as a result of swellings on the lower 

 ends of the second and third visceral arches and the intervening area. The 

 copula forms the root of the tongue; the tuberculum impar contributes the 

 middle portion; and the anterior part of the tongue arises from folds which 

 grow forward from the anterior portion of the tuberculum impar (fig. 284). 



