THE LIVER. SECRETION OP BILE. 587 



ever, to distinguish membranous parietes around these canals ; and he considers 

 that they are simply channelled-out in the parenchyma of the liver, the particles 

 of which form its sole borders. Professor Retzius, however, by a particular 

 method of preparation, has been able to demonstrate the existence of a basement- 

 membrane surrounding the biliary cells, and forming a plexus of hepatic ducts, 

 as described by Dr. Leidy. 1 



626. The biliary cells of the Human Liver (Fig. 157, B) are usually of a 

 flattened spheroidal form, and from l-1500th to 1 -2000th of an inch in diameter. 

 Each of them presents a distinct nucleus; and the cavity of the cell is occupied 

 by yellow amorphous biliary matter, usually having one or two large adipose glob- 

 ules, or five or six small ones, intermingled with it (a, 6). The size and number 

 of these, however, vary considerably, according to the nature of the food, the 

 amount of exercise recently taken, and other circumstances. If an animal be 

 very fat or well fed, especially with farinaceous or oleaginous substances, the 

 proportion of adipose particles is much greater than in an animal moderately 

 fed and taking much exercise (c). The size of the globules varies from that of 

 mere points, scarcely distinguishable from the granular contents of the cells 

 except by their intense blackness, up to one-fourth of the diameter of the cell. 

 The finely-granular matter is the portion from which the color of the cell is 

 derived; it seems to fill the space not occupied by the oil-globules; and it often 

 obscures the nucleus, so that the latter cannot be distinguished until acetic acid 

 is added, which makes the granular matter more transparent without affecting 

 the nucleus. A still greater accumulation of adipose particles in the biliary 

 cells gives rise, as was first pointed out by Mr. Bowman, 3 to the peculiar con- 

 dition termed " fatty liver" ( 628). 3 



627. The knowledge of the distribution of the Biliary ducts, and of the two 

 chief systems of Bloodvessels, in the lobules of the Liver, has enabled Mr. 

 Kiernan to give a most satisfactory explanation of appearances, by which Patho- 

 logical anatomists had been previously much perplexed. When the liver is in 

 a state of Anaemia (which rarely happens as a natural condition, although it 

 may be induced by bleeding an animal to death), the whole substance of the 

 lobules is pale, as represented in Fig. 158. In general, however, the liver is 

 more or less congested at the moment of death ; and this congestion may mani- 

 fest itself in several ways. The whole substance may be congested ; in which 

 case the lobules present a nearly uniform dark color throughout their substance, 

 their centres being usually more deeply-colored than the margins. An appear- 

 ance more frequently offered after death, however, is that represented at Fig. 

 159, and termed by Mr. Kiernan the first stage of Hepatic Venous congestion. 

 In this, the isolated centres of the lobules alone present the color of sanguine- 



1 See the account of his researches in " Muller's Archiv.," 1850. His method consists 

 in first macerating a piece of liver in ether, then drying it, cutting thin sections from it 

 in this condition, and soaking these in water until they become transparent. For a very 

 different view of the structure of the Liver, see Dr. Handfield Jones's papers in the 

 "Philosophical Transactions" for 1846 and 1849. 



2 "Medical Gazette," Jan. 1842. 



3 It has been recently maintained by Dr. Handfield Jones ("Medical Times," Jan. 31, 

 1852, p. 122), that "the cells of the liver are not the constant and necessary agents in the 

 secretion of bile, and that the occurrence of this secretion in them is rather to be viewed 

 as an accidental if not a pathological phenomenon ; the real function of the cell being to 

 produce the sugar out of the blood supplied to them, which is absorbed and carried off by 

 the hepatic vein." The arguments adduced in support of this opinion are, that in per- 

 fectly healthy livers of animals, bile is not ordinarily to be seen in the contents of the 

 cells, while it is very common in those of persons who have died of various diseases ; and 

 that in extracts made of the parenchymata of various livers, Pettenkofer's test gave very 

 little or no evidence of the presence of biliary matter. A far larger amount of research 

 is necessary, however, to establish such a novel and (at first sight) very improbable view. 



