OBSERVATIONS. 



lateral). This supports the contention of James Cantlie, 

 [Who, in his important paper, held that a line drawn 

 through the human gall bladder to the vena cava, at the 

 dorsal border, divided the liver into right and left parts. 

 This is well shown by a reference to the diagram of the 

 liver of Dasyurus Viverrinus, which represents the most 

 primitive Mammalian liver I have met. 



Fixation of the Liver. 



In Man the liver is separated dorsally with great dif- 

 ficulty. It is firmly held — apart from the suspensory 

 ligament — by close adhesions to the diaphragm. In the 

 Monotremes and Marsupials, however, the liver, as shown 

 in the diagrams of the diaphragmatic surface, is less 

 closely held dorsally. It can be easily separated. Firm 

 dorsal fixation of the human liver is an adaptation to the 

 erect position. This is associated, as in the case of the 

 spleen and pancreas, with compactness, and so displace- 

 ment and tendency to torsion is avoided. There is a 

 greater fixation of the liver of the Koala than in the other 

 Marsupials. This I regard as associated with the great 

 weight of the proximal colon and caecum (length of the 

 latter sometimes reaching 240 cm.), which are swung on 

 the common mesentery. The colon is suspended to the 

 pyloric region by a strong mesial fold, and so torsion is 

 prevented. As traction is transmitted to the liver through 

 the lesser omentum the advantages of a firm hepatic at- 

 tachment is obvious. Furthermore, when feeding, this 

 animal sits erect. 



Bile on (I Pancreatic Ducts. 



In both orders no separate entrance of the pancreatic 

 duct into the duodenum — apart from that associated with 

 the bile duct — is noted, i.e., the duct of Wirsung is the 



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