3S 2 



VESSELS OF THE LIVER. 



[sect. 162. 



lobules, as in the pig; from which, indeed, Kiernan has taken his 

 figures, Avhich are to some extent diagrammatical. If a small 

 branch of a hepatic vein be opened in the animal mentioned, there 

 are distinctly seen, through the walls of the vessel, polygonal areolae, 

 which represent the surfaces of the lobules directed towards, and 

 bounding the vein. 



A small vein, passing out of the middle of each of these sur- 

 faces, which Kiernan calls bases of the lobules, opens directly into 

 the larger vessel, and, when traced upon the opposite side, leads to 

 the interior of a lobule, where, arising from the capillary network 

 it never passes further to a second or third lobule. Thus there 

 comes out of every lobule always only one vein, which, on this 

 account, may be called vena intralohularis. The vessels, into which 

 these veins immediately open, are called by Kiernan sub-lobulares, 



because they run 

 along the basal sur- 

 faces of the lobules. 

 They are sometimes 

 larger in the pig, up 

 to 1'" to 2!" in dia- 

 meter, and then lie in 

 canals, surrounded by 

 the basal surfaces of a 

 certain number of lo- 

 bules ; sometimes they 



are finer or very fine, 



down to -3V", and then 



Fig. 151. 



Section of a very successful injection of the hepatic veins of 

 the rabbit; magnified 35 times. One, vena intralohularis, is 



visible in its whole course, the other only at its roots. The capil- 

 laries of the lobules coalesce in part, as also, at one place, two 

 venous radicles. From a preparation of Barling. 



they run only between 

 the lobules. The sub- 

 lobular veins unite to 

 form larger veins, which no longer directly receive vena? intralo- 

 bulares; and, accordingly, are limited only in part, or not all, by 

 the basal surfaces of the lobules, but by their lateral surfaces or 

 apices (capsular surfaces, Kiernan). Such veins, when they are 

 small, still receive sublobular veins from groups of lobules directly 

 bounding them; or, lastly, only larger veins, which present the 

 same conditions as they themselves. 



The relations of the vena? intralobulares are very simple. Everyone 

 of them penetrates in a straight direction into the axis of a hepatic 

 islet or lobule, splits up, somewhere about the middle, into two or 

 three main branches, which frequently once more divide. The 

 capillaries open not only into the extremities of these vein*, but 



