LIVER. 195 



The lobules are usually to be seen plainly on the surface of the 

 liver. Each lobule shows a radial arrangement of the liver 

 cells. These columns of liver cells radiate from the central 

 vein in the middle of the lobule, and are separated from one 

 another by blood capillaries. Both the capillaries and the 

 columns of cells anastomose frequently with one another. 



The gland cells of the liver are polyhedral, membraneless 

 structures, whose protoplasm is fibrillar and contains fine gran- 

 ules. In the periphery of the cell the protoplasmic network is 

 dense and possesses small meshes, while near the centre the 

 uieshwork becomes looser and more open. The protoplasm often 



FIG. 148. 



Beginning W^mBi ^KK^&W^rt cells 



of intenne-- 

 diate duct 



ifck.- j^Rfl} Connective 



Secretory 



' 



y / $jx 



' ^- 



From a section of a cat's pancreas. X 580. 



contains fat and bile droplets, glycogen, and pigment granules. 

 The cells contain usually one, but often two, round nuclei. 



Between the liver cells run the bile capillaries in such a 

 manner that they touch always two or more cells (Fig. 151). 

 There is thus always a, part of a cell between each bile capillary 

 and the nearest blood capillary. When many cells surround 

 a bile capillary, it may be, compared with the lumen of a sali- 

 vary gland tubule. When the capillary is between only two 

 cells, it appears as a small groove in each cell (Fig. 151). 

 When more than two cells touch the capillary, the latter is 

 situated at the angles of the cells. 



The bile capillaries possess no distinct wall of their own, 



