SECT. 



159] 



LOBULES OF THE LIVER. 



341 



branches of the portal veins. There thus arise small segments in the 

 liver, which contain only secerning parenchyma, capillaries, and the 



commencements of the hepatic veins; whilst in their interspaces, 

 together with the parenchyma and the capillaries, there exist, also, 

 the commencements of the hepatic ducts and the ultimate branches 

 of the portal vein" and hepatic artery, which, while they pass into 

 these segments, not only from one, but always from several dif- 

 ferent sides, and are strengthened and, in part, united by areolar 

 tissue, form, if not complete, at least partial zones around them. 



The livers of animals which present lobules (pig, polar bear, 

 J. Midler; Octodon Cummingii, Hyrtl) are of the greatest im- 

 portance for the knowledge of Fig. ho. 

 the structure of this organ, and ^^flflB ~~'~ >- 

 I may give here, accordingly, a 

 description of the structure of 

 If such a liver 

 on sections or 

 is ahvavs found 

 numerous small, 

 roundish, polygonal, not quite 

 regular, spaces of tolerably uni- 

 form size {^'" to 1 1'"), which 

 consist of the proper liver-paren- 

 chyma, and are separated by 

 whitish partitions readily visible 

 to the naked eye. If the cut 

 surface be scraped with the handle 

 of the scalpel, angular portions 

 of the liver, of the same size as 

 the spaces, become separated, and 

 the capsules which surround them 

 remain behind as empty compart- 

 ments, like a honeycomb. The 

 latter appear still more distinctly when a thin segment of the liver 

 is lightly kneaded in water with the fingers, then washed, and 

 viewed on a black ground, in which case many compartments re- 

 main almost completely closed, and thus present themselves still 

 nn ire distinctly as complete capsules. These capsules, however, are 

 not to be understood as if every hepatic lobule possessed its special 

 envelope; but the membranes, which form them, rather belong 

 always to several lobules in common, so that the whole presents a 

 con. trellis-work, whose partitions are all simple, and cannot 



the pig's liver 

 be examined 

 otherwise, it 

 divided into 



Section of the liver ot the pig, with an 

 opened hepatic vein ; slightly magnified, a. 

 Large vein, into which no intralobular veins 

 open; b. branches of the same with intra- 

 lobular veins, and the bases of the lobules 

 visible through them. After Kiernan. 



