346 ARRANGEMENT OF HEPATIC CELLS. [sect. 160. 



after Handheld Jones had already described the hepatic lobules as 

 being composed of solid rows of cells (see my Micr. Anal. II. 2). 



The only question that can arise is, whether the columns of 

 hepatic cells are surrounded by a delicate membrane, or whether 

 they are free and directly applied to the capillary network. The 

 former view has been advocated by many observers, especially by 

 Kruhenberg , Schroder van der Kolk, Retzim, Theile, Backer, and 

 Leidy ; but none of these has been able to demonstrate the exist- 

 ence of such a membrane beyond all doubt. Even L. Beale, to 

 Avhom we are indebted for a most elaborate paper on the liver, and 

 who has brought forward many facts in favour of the existence of 

 delicate tubes of basement membrane, in which the liver-cells lie, 

 is obliged to confess, that in many cases this membrane cannot be 

 demonstrated. Beale says (On some Points in the Anatomy of the 

 Liver, p. 44), ' The circumstances above enumerated impress me 

 with the idea, that the liver is orginally composed of two distinct net- 

 works, which intimately interdigitate Avitli or fit into each other — 

 one containing the secreting cells, the other the blood. As de- 

 velopment advances, the Avails of these two sets of tubes gradually 

 become incorporated, except in those situations where the capillary 

 network is less dense, or where the meshes of the cell-containing 

 network are more widely separated from each other, in which cases 

 a distinct limitary membrane to the tubes containing the liver-cells 

 can be demonstrated in the adult/ Further on he remarks : — 

 'Under some circumstances, then, it is demonstrable that the 

 basement membrane of the cell-containing network is distinct 

 from the walls of the capillaries ; but in the greater part of the 

 lobule, where the two membranes come into close contact, they arc 

 incorporated, so that really the majority of the liver-cells, except 

 where they are in contact with each other, are surrounded with 

 blood, from which they are only separated by a thin layer of de- 

 licate structureless membrane.' 



From this quotation, it may be seen that Beale agrees with me 

 in one great point, viz., that the membranes around the network 

 of liver-cells cannot be demonstrated in the interior of the lobule; 

 on the other hand, the excellent observations of the able Professor 

 of King's College have convinced me that such membranes really 

 exist in the exterior parts of the lobules, at the points of commu- 

 nication between the smallest biliary ducts and the network of 

 the secreting cells. But I cannot agree in the opinion which he 

 expresses, that the liver- cells do not exactly fill the delicate tubes 

 in which they lie, and that the bile passes along the tubes in the 



