710 BILE-CAPILLARIES. [BOOK n. 



between the hepatic cells will be seen to be continuous with a 

 larger quantity of the same blue material occupying the lumen 

 of one of the minute bile-ducts as it abuts on the margin of the 

 lobule. These minute canals are therefore continuous with the bile- 

 ducts; they are the terminations of the bile-ducts within the lobules, 

 and indeed not only may they be injected during life with sodium 

 sulphindigotate, but injection material may, though with difficulty, 

 be driven into them backwards along the bile-ducts. They are 

 spoken of as bile-capillaries ; the name perhaps is not a very 

 desirable one, but it has been generally adopted. 



We said just now that each hepatic cell touched a blood vessel 

 by at least one of its surfaces, we may now add that each hepatic 

 cell has at least one side, and generally more than one side, grooved 

 to form a bile-capillary. Since each side thus grooved is in contact 

 with the corresponding side of a neighbouring cell, it cannot run 

 alongside a blood vessel. Hence between a bile-capillary and a 

 blood vessel some amount of cell-substance is always interposed. 

 The relative position of the bile-capillaries and blood vessels 

 may be illustrated by taking a cube and converting it into a 

 polygon by bevelling down the angles of the sides, leaving in the 

 first instance those of the upper and lower faces untouched. 

 The blood vessels may then be considered as running down 

 the bevelled edges, while bile-capillaries run along the middle 

 lines of the sides. Two such cubes placed end to end might 

 represent a thin small islet of cells in one of the smaller shorter 

 radial meshes of the vascular network ; and then the angles 

 of the upper and lower face of the conjoined cubes would have also 

 to be bevelled for the cross bars of the network. Frequently, as we 

 have said, the cells lie two abreast in a mesh of the vascular 

 network ; then of course in the model the angles of the surfaces 

 in contact would not have to be bevelled since no blood vessels run 

 between them. If several such bevelled cubes were built up into 

 a model, it would be seen that the network of bile-capillaries 

 runs along the middle of the surfaces between the blood vessels, 

 forming nodal points where cells are in contact with each other by 

 their surfaces, and leaving some amount of cell-substance between 

 the bile-capillary and the blood vessels. This at least may be 

 taken as the typical arrangement, when the network of bile- 

 capillaries is most complex. But many cells have the lumen of a 

 bile-capillary on one side only ; and occasionally a bile-capillary is 

 seen in section at the point of convergence of three cells after 

 the fashion of an ordinary alveolus. 



When a bile-duct abuts on the margin of a lobule the lumen, 

 as we have previously said, seems suddenly to come to an end. 

 The flattened cells lining the ductule or terminal portion of the 

 duct suddenly change into large hepatic cells, marginal cells of the 

 lobule, which appear to be completely in contact with each other 

 and to block up the ductule. But along the sides of these 



