170 



NORMAL ANATOMY OF THE LIVER. 



the frog ending in twig-like terminations. 

 Kiernan inclines to the opinion that they termi- 

 nate in loops, although he says nothing which 

 could lead us to suppose that he rejects the 

 possibility of their terminations being ccecal. 

 Both authors agree that they end by closed 

 extremities. It is this plexus which constitutes 

 the true glandular portion of the liver. 



Miiller, in reference to the terminations of 

 the ducts in anastomosing plexuses, states, that 

 the history of the development of the organ is 

 opposed to the belief in the existence of anas- 

 tomoses. Certainly, if we are to credit the 

 principle which he himself has established for 

 the development of glands, viz. that " however 

 various the form of the elementary parts, all 

 secreting glands without exception follow the 

 same law of conformation," the same process 

 must take place in all ; and analogy would lead 

 us to infer that a plexiform anastomosis would 

 be the arrangement of the terminal ducts in so 

 complicated a gland as the liver of the adult, 

 whatsoever it may happen to be in the unde- 

 veloped organ of the embryo. That there is 

 nothing irrational in this opinion we would 

 turn for proof to another page of his Physiology, 

 where he observes, " in the scorpion, as I have 

 discovered, the tubes (of the testis) anastomose, 

 forming loops." Again, he says, " Lauth has 

 but once seen a seminal canal ending with a 

 free extremity in the human testis. Krause has 

 seen such free ends of the tubuli seminiferi 

 frequently, and confirms the opinion of their 

 terminating in that way as well as by anasto- 

 mosis. Lauth attributes the circumstance of 

 free extremities of the tubes being so seldom 

 seen to their uniting with each other so as to 

 form loops. He describes the division and 

 reunion of the tubes to be so frequent that in a 

 small portion which he spread out, and in 

 which there were about forty-nine inches of 

 tube, he found about fifteen anastomoses. It 

 is, however, only towards their extremities that 

 the seminal tubes anastomose thus freely. The 

 discovery of the anastomoses of the seminal 

 tubes is perfectly original." Krause observes 

 the same fact also with regard to the uriniferous 

 ducts. Now I would ask why, if the ducts 

 of the seminal gland and uriniferous gland 

 anastomose so freely, the ducts of the biliary 

 gland should not do the same ? And why, if 

 the anastomoses of the seminal ducts be a dis- 

 covery so original, the less easily demonstrable 

 fact of the anastomoses of the biliary ducts, 

 discovered by Kiernan, may not be equally 

 original ? I speak from laborious research upon 

 this subject, and surely there cannot be a com- 

 parison between the difficulty of unravelling 

 the simple ducts of the testis and the compli- 

 cated and minute masses of the biliary ducts, 

 an aggregation so intricate that Miiller acknow- 

 ledges it " difficult to decide the question." 

 The above facts of the anastomoses of the 

 seminal and uriniferous ducts would, in my 

 mind, were other evidence wanting, be a cir- 

 cumstance powerfully aiding my belief in the 

 anastomoses of the biliary ducts; but the sub- 

 ject is not without its proofs, and these, as it 

 appears to me, from careful examination, incon- 



testible. " The left lateral ligament," says 

 Kiernaa, " may be considered as a rudimental 

 liver, in which this organ presents itself to our 

 examination in its simplest form. From that 

 edge of the liver connected to the ligament, 

 numerous ducts emerge, which ramify between 

 the two layers of peritoneum of which the 

 ligament is composed." " These ducts, the 

 smallest of which are very tortuous in their 

 course, divide, subdivide, and anastomose with 

 each other. They are sometimes exceedingly 

 numerous, two or three of them in such cases 

 being of considerable size; some of them, as 

 Ferrein" (by whom they were discovered) 

 " says, frequently extend to the diaphragm and 

 ramify on its inferior surface. They sometimes 

 extend only half way up the ligament, where 

 they divide into branches, which forming arches 

 (Jig- 41,) return and descend towards the liver, 



The left lateral ligament, in which are teen the in- 

 jected biliary duett with their anaatomoiei. After 

 Kiernan.* 



anastomosing or being continuous with other 

 ducts issuing from it. The spaces between 

 the larger or excreting ducts are occupied 

 by plexuses of minute or secreting ducts." 

 " Branches of the portal and hepatic veins, 

 with arteries and absorbents, also ramify in the 

 ligament, which, including between its layers 

 a plexus of secreting and excreting ducts, with 

 bloodvessels ramifying on their parietes, ad- 

 mirably displays the structure of the liver." 

 The same appearances are seen in the bands 

 which sometimes arch over the vena cava and 

 longitudinal fissure, when they are sufficiently 

 thin. 



The hepatic ducts are extremely vascular, 

 and in a well-injected liver are always com- 

 pletely covered with the ramifications of the 

 hepatic artery. The rugae upon their internal 

 surface are formed by large vessels, " arteries 

 as well as veins," which are distributed beneath 

 the mucous membrane. This membrane, seen 

 beneath the microscope, appears plaited over 

 every part of its surface by innumerable lami- 

 nated papillae of a semilunar form. The vessels 

 distributed upon these papillae consist of an 

 artery which ascends upon each side of the 

 lamina, and divides into a beautiful net-work 

 of capillaries which are collected after their 

 distribution into a small vein and returned to 

 the portal vein. " It is," says Kiernan, " to 

 the rupture of the delicate vessels forming these 



* I have carefully examined this preparation 

 and pledge myself to its accuracy. 



