740 STRUCTURE OF LIVER. [BOOK n. 



several lobules, the septa of connective tissue denning the lobules 

 from each other being the terminations of Glisson's capsule 

 carrying the three sets of vessels. The small branches of the 

 portal vein thus reaching the surface of the lobules, and running 

 and anastomosing freely between the lobules, are spoken of as 

 interlobular veins. Thus each lobule is provided, at different parts 

 of its circumference, with two, three or more interlobular veins, 

 accompanied in a manner which we shall describe by divisions of 

 the bile-duct and hepatic artery, all being embedded in a (variable) 

 quantity of connective tissue. 



Each lobule at one part of its circumference rests directly, with 

 the intervention of hardly any connective tissue at all, upon a 

 small vein which is not part of the portal vein, but which when 

 traced out is found to pass into and form the hepatic vein ; it is 

 called a sublobular vein. A lobule in fact, though generally poly- 

 hedral as seen in sections of the liver, may be considered as some- 

 what of the form of a broad inverted flask, the neck of which rests 

 directly on a sublobular branch of the hepatic vein, and upon the 

 polygonal body of which, surrounded by more or less connective 

 tissue, abut at various points interlobular branches of the portal 

 vein. 



446. The network of interlobular veins surrounding the 

 circumference of a lobule gives origin to a number of rather wide 

 capillary vessels which run in a radial direction towards the middle 

 of the lobule ; these are connected by cross capillaries, which 

 however are shorter and less abundant than the radial capillaries, 

 so that the meshes are elongated, more or less rectangular spaces 

 converging radially towards the centre of the lobule. Towards 

 the middle of the lobule the capillaries merge into a single vein, 

 called an intralobular vein, which, running down the neck of the 

 flask, and receiving the capillaries of the neck as it goes, falls into 

 the sublobular vein spoken of above. 



The elongated meshes of this capillary network converging 

 radially towards the intralobular vein at its beginning in the 

 body of the flask-like lobule and as it is continued along the neck 

 of the flask, are occupied by relatively large polygonal nucleated 

 cells, which we shall presently describe in detail as hepatic cells. 

 The width of a mesh is generally such as to admit one or two 

 cells abreast, but its length admits several cells ; hence the cells 

 are arranged in narrow radiating broken columns converging 

 towards the middle of the lobule. 



The columns of cells and the meshwork of capillaries prac- 

 tically constitute the whole of the lobule, for besides a minimum of 

 connective tissue forming an adventitia to the capillaries, certain 

 lymphatic passages afforded by this adventitia, and extremely 

 minute passages which form the beginnings of the bile-ducts, and 

 of which we shall speak later on, nothing else is present. The 

 lobule in fact consists first of a vascular framework of capillaries 



