TIIK LIVER 



411 



as they approach the central vein produce great irregularities in the 

 arrangement and length of the cell cords. Each cord, however, reaches 

 the periphery of the lobule after a more or less tortuous course, and it 

 is here that the secretory bile capillaries, which are found within the 

 cell cords, become continuous with the minute bile ducts of the portal 

 canals. 



FIG. 384. A LOBULE OF THE HUMAN LIVER, SEEN IN TRANSECTION. 



It is outlined by three small portal canals and contains a single central vein. 

 Hematein and eosin. Photo. X 50. 



THE BILE CAPILLARIES. The bile capillaries occur as secretory 

 canaliculi between the opposed surfaces of the hepatic cells. They are 

 thus found within the cell cords and stand in the same relation to the 

 hepatic cells as though each cell cord formed a tubule whose capillary 

 lumen, the bile canaliculus, was surrounded by only two secreting cells, 

 whereas in other tubular glands a larger number of cells encircle the 

 lumen of the secreting tubule. Hence the bile canaliculi and the blood 

 capillaries are never in contact, but are always separated by at least 

 one-third to one-half the diameter of a hepatic cell. The bile canaliculus 

 occurs on that surface of the hepatic cell which is in contact with other 



