GLANDS. 419 



the intestines to its termination in the lobules of the liver, may 

 then be compared either to two trees joined by their trunks, 

 or to a single uprooted tree. The preceding account renders 

 it evident that it is from the blood contained in the portal 

 vein that the secretion of bile takes place. 



In those cases in which the blood-vessels become injected 

 from the biliary ducts, it is usually the portal system which 

 receives the greater part of the injection; and this is thrown 

 into it at different points irregularly, so that there are no 

 definite zones of capillaries marking out the lobules ; but 

 masses of capillaries are seen here and there arranged without 

 any certain order. 



Hepatic Artery. The hepatic artery is the nutritious 

 vessel of the liver; it supplies the vessels of the hepatic 

 ducts, the vasa vasorum, and the capsule of the liver. 



It is distributed principally, however, to the capsules 

 covering the lobules, and to the general capsular investment 

 of the liver. 



Some of the interlobular or lesser capsular branches pene- 

 trate the substance of the lobules, and terminate in the portal 

 capillaries of the lobular plexus. (See Plate LVL./?y. 2.) 



The outer capsular branches are remarkable for their great 

 length, and the simple manner in which they divide and sub- 

 divide. 



The hepatic artery does not anastomose with the hepatic 

 vein. 



Pathology. 



The pathology of the liver may be divided into two sec- 

 tions, according as the seat of the disease affects its secreting 

 or vascular apparatus. 



Secreting Apparatus. 



Two abnormal conditions of the secreting cells of the liver 

 have been noticed : in the first, biliary engorgement, the cells 

 are seen to contain a greater quantity of biliary matter, in 

 the form of globules of various sizes, than ordinary ; in the 

 second, fatty degeneration of the liver, the cells are laden 



L L 3 



