THE LIVER. 115 



it arises from the vena intralobular is and often appears 

 stellate. 



By the more complete filling up of the capillary network, it 

 may happen, and, according to Theile, this is in fact the usual 

 case in the majority of human livers, that the fissures inter- 

 lobulares disappear, the brown substance representing a net- 

 work, and the yellow, occurring in isolated spots. I find, as I 

 have stated above, that perfectly fresh livers are, for the most 

 part, uniformly coloured throughout. Kiernan describes, in 

 children, even a reversal of the colouring, which he considers to 

 be dependent upon congestion, more particularly of the vena 

 portce, the external portions of the hepatic lobes being thus 

 more injected. Neither Theile nor I have hitherto noticed this 

 form.] 



§160. 



Hepatic celh and cell-networks. — Every hepatic islet con- 

 tains two elements ; 1. a network of capillaries, which, on the 

 one hand, is continuous with the finest portal branches, and 

 on the other, unites into the intralobular vein, one of the roots 

 of the hepatic vein; and 2. an interlaced tissue of delicate 

 columns, composed of nothing but cells, the so-called hepatic 

 cells, in close and immediate apposition. These two net- 

 works are so interwoven that the interstices of the one are 

 completely filled by the solid portions of the other and leave 

 no interspaces, at least when the vessels contain blood or are 

 injected. Not a trace of biliary ducts is to be observed in 

 this network : they are first met with at the periphery of 

 the hepatic islets, where also the finest portal branches occur, 

 without its having been possible, hitherto, to make out, 

 directly, their connection with the hepatic-cell-network, which 

 is indubitably the secreting portion of the liver. 



The hepatic cells, which may be isolated with the greatest 

 ease, 1 have a diameter of 0*008 — 0*01 2'" on the average, 



1 [This is true of the hepatic " cells" of Man and many Mammalia, but not of all. 

 In the Rat, we could find no demarcation of the hepatic tissue into cells, the tissue 

 resembling very nearly that of the spleen. In Fishes, Dr. Handfield Jones has pointed 

 out the existence of all varieties in this respect, from free " nuclei," with oily and 

 granular matter scattered through a matrix, up to perfectly formed " cells." In the 

 Pigeon, the same author finds no fully formed cells, nor in the Duck; and he there- 



