PERICARDIUM, PLEUROPERITONEUM, DIAPHRAGM AND MESENTERIES. 381 



with the transverse mesocolon and transverse colon (Fig. 341). During the 

 first or second year after birth the two lamella; fuse with each other caudal 

 to the transverse colon to form the greater omentum of adult anatomy. 



Diaphragm. ._ 

 Liver-.,, 

 Lesser omentum.. 



Pancreas-^^ 

 Bursa omentalis--.. 



Stomach 



Greater omentum 



Duodenum 



Transverse mesocolon 



Transverse colon 



Mesentery of 

 small intestine 



Small intestine 



Fig. 339. 



Diaph. - 



Fig. 340. Fig. 341. 



Figs. 339, 340 and 341. — Diagrams showing stages in the development of the bursa omentalis, the 

 greater omentum, and the fusion of the latter with the transverse mesocolon. Diagrams 

 represent sagittal sections. For explanation of lettering in Figs. 340 and 341 see Fig. 339. 



The Lesser Omentum. — It has already been noted that the liver grows into 

 the caudal portion of the septum transversum (p. 376). Since the ventral 

 mesentery in the abdominal region, or the ventral mesogastrium, is primarily 



