290 



PRACTICAL HISTOLOGY. 



[XXVI. 



lobule. Notice that the shape of the mesh work of capillaries is 

 different at the centre and periphery. Between the lobules and 

 outside each lobule branches of the portal vein. 



7. Liver of Rabbit, Injected (fig. 280), e.g., a section with its 

 blood-vessels injected with different colours, e.g., P.V. red (carmine 

 gelatine) and H.Y. blue (Berlin-blue gelatine). Also a section 

 where all the blood-vessels are injected with a mass of one colour. 

 In a double injection the red and blue masses do not always occupy 

 the area corresponding to the blood-vessel into which they were 

 injected, but with care such a piece can be found in an injected 

 liver. The arrangement of the blood-vessels corresponds to that 

 seen in the uninjected specimens, only in the former the blood- 

 vessels are more prominent than the cells. 



(a.) (L) Observe the in terlobular* veins round the periphery of 

 the lobule, the central or intralobular vein, and the plexus of 



Fibrous 

 wall. 



FIG 281. .uiterlobular Bile-Duct. 



FIG. 280. Injected Blood- Vessels of a Lobule 

 of a Rabbit's Liver. 



capillaries connecting the two. The capillaries converge towards 

 the centre of the lobule, where the meshes are more elongated. 

 At the periphery of the lobule the capillary mesh work is more 

 polygonal. 



Very instructive also are those with only one set of vessels 

 injected, e.g., portal or hepatic. They serve to show the capillaries 

 belonging to each area within a lobule. 



8. Injected and Stained Section. A beautiful preparation is 

 obtained by staining a section (blue injection) with picro-lithium 

 carmine. In it the vessels are blue, the cells yellow, and the nuclei 

 of the latter red. 



9. Bile-Ducts. Mount in balsam a section of a rabbit's, or, better 

 still, a guinea-pig's Iryer in which the bile-ducts have been injected 

 with a concentrated watery solution of Berlin-blue. It is very 



