134 GLANDS. 



The walls of the gall-bladder are composed of the 

 same elements as those of the larger biliary ducts. 

 Its mucous membrane has numerous folds and rugse 



nute Structure of the Liver" in which, after very thorough investigation 

 of the subject, he arrives at the conclusion that Kiernan's hypothesis is 

 correct, and that the biliary plexus is truly demonstrable, although, after 

 long and laborious research, he was not able to demonstrate the existence 

 of the membrane forming the Avails of the tubes composing it. He 

 speaks, however, with confidence, of the network of tubes, or biliary 

 plexus, containing the secreting cells of the liver (hepatic cells), as occu- 

 pying the interstices of the vascular plexus of the lobule so that the two 

 sets of tubes, biliary and vascular, interlace with each other accurately, 

 the walls of the bile-tubes being everywhere so closely adherent to the 

 external surfaces of the blood capillaries that the former were riot sus- 

 ceptible of separate demonstration (p. 59 et seq.). 



In a Monograph by Dr. Lionel S. Beale (on some points in the Ana- 

 tomy of the Liver of Man and Vertebrate Animals, London, 1856), the 

 following passage occurs in the summary of his able and interesting 

 investigations on this subject : 



" The liver cells lie within a tubular network of basement membrane, 

 which separates them from the walls of the capillaries. In many cases, 

 however, these thin membranous tubes cannot be separated, and are, no 

 doubt, incorporated with each other." 



" The cell-containing network is directly continuous with the most 

 minute ducts, which ramify at the circumference of the lobule, and it 

 . terminates in the centre by loops, which lie close to the intralobular 

 vein.' 1 (p. 74.) 



Both Lereboullet and Beale describe the tubes composing the " cell- 

 containing network" as larger in diameter than the " minute ducts," 

 which are the radicles of the hepatic duct. " The tubes of the cell-con- 

 taining network are about T oV^ tn of an inch in diameter, or more, but 

 the finest ducts are commonly not more that 3 oVo tn ? an< ^ tnev are ften 

 seen even less." . . . "The smallest ducts are lined with a very delicate 

 layer of epithelium, composed of flattened cells of a circular form, con- 

 trasting remarkably with the large secreting cells" the hepatic cells 

 proper, which occupy the cell- containing network, or biliary plexus. 

 (Beale, p. 74.) 



In addition to the evidence we have quoted, which sets forth what we 

 believe to be the true anatomy of the liver in relation to the point in 

 question, the monographs of Lereboullet and Beale may be advanta- 



