12 THE LIVER, BY EWALD BERING. 



be found. Beale * states that in children the tubes can be easily 

 isolated from the capillary walls, but that in adults this can only be 

 accomplished with difficulty, or not at all. According to the descrip- 

 tion of the structure of the lobules given above, if a membrana pro- 

 pria exist around the liver cells, it must also invest the capillaries, so 

 that the membrane which I, with other observers, have considered to 

 be merely the capillary wall, would then consist, not only of the 

 capillary wall, but also of the membrane. Frey is of opinion that this 

 membrane encloses the perivascular lymph space, so that the lymph is 

 contained between it and the capillary wall. 



THE CELLS OF THE LIVER. The gland-cells of the liver 

 of Man, discovered by Purkinje and Henle, only come under 

 observation when they have ceased to live. If the surface of 

 the liver exposed by section be scraped with the blade of a 

 knife, a fluid is obtained, in which, besides other elements, 

 numerous hepatic cells float, some of which are isolated, whilst 

 others are united into groups. These appear as round or 

 sometimes angular bodies, with an average diameter, according 

 to Kolliker, of O'OIS 0'026 of a millimeter, and consist of a 

 colourless, finely granular material without any investing 

 membrane. They contain in their interior one, or more rarely 

 two, ellipsoidal nuclei, which, according to the same observer, 

 have a diameter varying from 0'006 to 0'009 of a millimeter, and 

 are sometimes discoverable with difficulty. The cell substance 

 also frequently contains small granules or groups of granules 

 of a yellowish or brown substance (biliary pigment), and 

 strongly refracting molecules of various size (fat). The latter, 

 when small, are usually numerous ; but there is sometimes a sin- 

 gle large globule invested by a thin layer of the cell substance. 

 Such cells are frequently of unusually large dimensions. 



Cells detached from hardened livers are polyhedric, and of 

 the most varied form, often presenting pointed angular pro- 

 cesses, whilst their edges or surfaces seen in profile are in 

 some parts sharply defined by a dark line, and in others 

 softened off and ragged. The cell substance is darkly granular, 

 the nucleus very clearly defined, and often presenting a double 

 contour. 



* On some Points of the Anatomy of the Liver. London, 1856. 



