OBSERVATIONS. 



Diffuse or Compact Liver. 



If we take the Platypus at one end of the Mammalian 

 scale, and Man at the other, a striking feature of the liver 

 is the multiplicity of lobes (divisibility of hepatic tissue) 

 in the former, and the compactness or tendency to uni- 

 fication in that of the latter. This we find true, not only 

 as regards the liver, but also the spleen and pancreas. 

 For the erect attitude consolidation would be advan- 

 tageous for fixation, and so, amongst other things, the 

 tendency to torsion lessened. 



Development of the Mammalian Liver. 



The hypoplastic diverticulum, or liver bud, springs 

 from that portion of the fore gut which will afterwards 

 become the second portion of the duodenum. Portion of 

 this gives rise to the liver tissue, which at first consists of 

 right and left masses of cells, and portion gives rise to 

 the gall bladder and main ducts. It is interesting to note 

 that all the specimens examined conform generally to a 

 simple plan, namely, right and left lateral portions or 

 masses, with the portal vein, and gall bladder, cystic, and 

 common ducts, as a common stem. On the right side 

 hepatic and portal branches are traced to the right por- 

 tion (right cystic and right lateral), and on the left side 

 branches pass to the left portion (left cystic and left 



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