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injection, so that the walls of contiguous tubes meet, while the 

 capillary vessel between them becomes so compressed as not to be 

 recognizable. 



The injection often forms a sharp line towards the capillary ves- 

 sels on either side of the tube in which the cells lie, and gradually 

 shades off towards the centre of the tube. 



The cells which escape into the surrounding fluid from injected 

 specimens often have portions of injection adhering to them. 



If a section be made at right angles to the intralobular vein, the 

 cells are seen to form lines radiating from the centre towards the 

 circumference of the lobule, as authors have before described. 

 These lines of cells are really tubes of basement membrane, com- 

 municating with each other at intervals by narrow branches. In 

 injected specimens the walls of the tube can be demonstrated, and 

 are seen to be distinct from the capillary vessels. 



In the foetus, the cells are seen to be separated from the cavity of 

 the vessels by two lines separated by a clear space. One of these 

 lines is caused by the outline of the tube containing the cells, the 

 other is that of the capillary wall. 



The author supposes that, originally, the liver is composed of a 

 double network of tubes (cell-containing network and capillary net- 

 work), the walls of which in most situations become incorporated, 

 so that the secreting cells are only separated from the blood by one 

 thin layer of basement membrane, which is very permeable to water 

 in both directions, but the greatest force which can be applied with- 

 out causing rupture is incapable of forcing bile through it. 



Of the contents of the tubular network of basement membrane, and of 

 the arrangement of the cells within it. 



Within the tubular network lie the hepatic cells, with a certain 

 quantity of granular matter and cell debris, and, in some instances, 

 free oil-globules and granules of colouring matter. The cells are 

 not arranged with any order or regularity. Some observers have 

 endeavoured to show that the hepatic cells are arranged in a definite 

 manner. Professor Lereboullet, one of the latest writers on this 

 subject (1853), describes the cells as forming double rows. The 

 two rows of cells may be separated by injection, and he gives two 

 diagrams to illustrate their arrangement. The author has never 



