TERMINATION OF NERVES IN THM LIVER. 451 



found absent frequently in otherwise successful preparations, 

 and the fibres usually are not more than half a dozen, each 

 separated from the other by a considerable interval of space. 



For tracing the nerve-fibres further to their termination it is 

 necessary to resort to the special sections which I have referred 

 to, namely, those which decrease in thickness from one edge to 

 the opposite one. In a section of this sort, if the thick edge 

 includes a longitudinal view of one of the interlobular canals, 

 every facility is thereby aflforded for following these fibres. A 

 uniformly thin section is not of much value for this purpose, as 

 in it the fibres can be followed but a short distance, on the 

 average equal to the combined diameter of four or five cells, 

 and the connection of the smaller with the larger fibres is diffi- 

 cult to make out. Part of a section prepared in the manner 

 described is drawn in fig. 1, which represents the border of a 

 hepatic lobule. At such a point are found medium-sized fibres 

 coloured deep violet, always with a clearly defined border, quite 

 difi'erent in this respect from connective-tissue fibres. One 

 sees them arise from the large deep violet fibres of the inter- 

 lobular canals, often as a direct continuation, without branchinsr 

 until after they enter the lobule. They are not numerous, 

 there being usually two of them to each capillary channel, and 

 they run between the capillary wall and the hepatic cells. 

 They are easily distinguished with a low power objective. At 

 first view they appear to form a network of anastomosing fibres, 

 but a further examination shows that the branches of these 

 fibres cross rather than join each other. Fibres of such a 

 diameter are never found outside the capillary channels, that 

 is, they do not penetrate between the liver-cells. These fibres 

 belong to what I have denominated the coarse intralobular 

 plexus. They possess no nuclei and branch at acute angles, 

 the resulting branches being either quite as large as the original 

 trunks or much finer. The large ones may be considered as 

 belonging to the plexus just mentioned. The finer may be 

 resolved into two classes : a perivascular plexus or network and 

 an intercellular one. The perivascular network can be best 

 seen when one looks from above into a capillary channel cut 



