330 



EMBRYOLOGY. 



capillaries and the hepatic cells, to which there also corresponds a greater 

 complication in the distribution of the capillaries of the blood-vessels. By 

 means of all this the original tubular structure of the gland becomes almost 

 entirely obliterated in the fully developed organ. In the adult, as is well 

 known, the parenchyma of the liver is divided by means of connective-tissue 

 partitions into small lobes (acini or lobuli). At the beginning of development 

 nothing is seen of the lobulated structure, because all the hepatic cylinders 



are united into a network. Detailed in- 

 formation concerning the development of 

 the lobules is wanting. 



Now a few words concerning the 

 ligaments and the conditions of form 

 and size which the liver presents up to 

 the time of birth. 



The ligamentous apparatus, as was 

 remarked in the beginning, is preformed 

 in a ventral mesentery (the Vorleber). 

 Owing to the fact that the two hepatic 

 sacs grow out from the duodenum 

 into this ventral mesentery, and by 

 continual branching produce the right 

 and the left lobes of the liver (figs. 184, 

 185, and 188), the ventral mesentery 

 becomes divided into three portions : 

 first, a middle part, which furnishes 

 the peritoneal covering for both lobes 

 of the liver; secondly, a ligament which 

 proceeds from the front convex surface 

 of the liver in a sagittal direction to the 

 ventral wall of the body, extending as 

 far as the navel and embracing in its 



free margin the subsequently disappearing umbilical vein (ligamentum 

 suspensorium and teres hepatis, figs. 184, 188 Is) ; and thirdly, a liga- 

 ment which proceeds from the opposite, concave or portal surface of 

 the liver to the duodenum and the lesser curvature of the stomach, 

 and which contains the ductus choledochus and the afferent hepatic 

 blood-vessels (omentum minus, which is divided into the ligamentum 

 hepato-gastricum and hepato-duodenale). (Figs. 184 Ihd and 188 Jen.} 

 The lesser omentum or omentum minus soon loses its original 

 sagittal position and is stretched out into a thin membrane running 

 from right to left (fig. 166 kri) ; this is due to the fact that the 

 stomach undergoes the previously described displacement, and moves 



Fig. 188. Diagram to show the 

 original positions of the liver, 

 stomach, duodenum, pancreas, 

 and spleen, and the ligamentous 

 apparatus pertaining to them. 

 The organs are seen in longi- 

 tudinal section. 



I, Liver ; m, spleen ; p, pancreas ; 

 dd, small intestine ; dg, vitelline 

 duct ; bid, ccecum ; md, rectum ; 

 kc, lesser curvature, gc, greater 

 curvature of the stomach; meg, 

 mesentery ; Ten, lesser omentum 

 (lig. hepato-gastricum and hepato- 

 duodenale); Is, ligamentum sus- 

 pensorium hepatis. 



