520 STRUCTURAL ANATOMY OF THE LIVER. 



nences on their surface. When divided longitudinally, they have a foli- 

 ated appearance, and transversely, a polygonal outline, with sharp or 

 rounded angles, according to the smaller or greater quantity of Glisson's 

 capsule contained in the liver. Each lobule is divided upon its exterior 

 into a base and a capsular surface. The base corresponds with one ex- 

 tremity of the lobule, is flattened, and rests upon an hepatic vein, which 

 is thence named sublobular. The capsular surface includes the rest of the 

 periphery of the lobule, and has received its designation from being en- 

 closed in an areolar capsule derived from the capsule of Glisson. In the 

 centre of each lobule is a small vein, the intralobular, which is formed by 

 the convergence of six or eight minute venules from the rounded promi- 

 nences of the periphery. The intralobular vein thus constituted takes its 

 course through the centre of the longitudinal axis of the lobule, pierces 

 the middle of its base, and opens into the sublobular vein. The periphery 

 of the lobule, with the exception of its base, which is always closely at- 

 tached to a sublobular vein, is connected by means of its areolar capsule 

 with the capsular surfaces of surrounding lobules. The interval between 

 the lobules is the interlobular fissure, and the angular interstices formed 

 by the apposition of several lobules are the interlobular spaces. 



The lobules of the centre of the liver are angular, and somewhat smaller 

 than those of the surface, from the greater compression to which they are 

 submitted. The superficial lobules are incomplete, and give to the sur- 

 face of the organ the appearance and all the advantages resulting from an 

 examination of a transverse section. 



" Each lobule is composed of a plexus of biliary ducts, of a venous plexus, 

 formed by branches of the portal vein, of a branch (intralobular), of an 

 hepatic vein, and of minute arteries ; nerves and absorbents, it is to be pre- 

 sumed, also enter into their formation, but cannot be traced into them." 

 " Examined with the microscope, a lobule is apparently composed of nume- 

 rous minute bodies of a yellowish colour and of various forms, connected 

 with each other by vessels. These minute bodies are the acini of Malpighi." 



" If an uninjected lobule be exa- 



Fig. 230 * mined and contrasted with an injected 



lobule, it will be found that the acini 

 of Malpighi in the former are identi- 

 cal with the injected lobular biliary 

 plexus in the latter, and the blood- 

 vessels in both will be easily distin- 

 guished from the ducts."f 



Glissotfs capsule is the areolo- 

 fibrous tissue which envelopes the he- 

 patic artery, portal vein, and hepatic 

 duct, during their passage through the 

 right border of the lesser omentum, 

 and which continues to surround them 

 to their ultimate distribution in the 

 substance of the lobules. It forms for 



* Horizontal section of three superficial lobules, showing the two principal systems 

 u* blood-vessels. (Kiernan.} 



f The Anatomy and Physiology of the Liver, by Mr. Kiernan, Phil. Trans. 1833, 

 Jrom which this and the other paragraphs within inverted commas, on the structure of 

 the liver, are quoted 



