THE DENTAL PULP 215 



to the collection or drawing together of these fine fibres of 

 the plexus into larger strands where they enter the odonto- 

 blast layer (fig. 130). As shown above, however, it is seen 

 that these larger strands passing to the dentine are processes 

 of the 'end cells'. 



The bundles of neurofibrils vary very much in size, and 

 even in the deep plexus many much larger strands are seen 

 passing across it to the * end cell ' layer. At the crown of the 

 pulp these strands of neurofibrils are so much larger that 



^ 



FIG. 130. Neurofibrils entering the dentine at the 

 cornu of the pulp. ( x 800. ) 



it appears in specimens in which the ' end cells ' are not 

 stained that they pass direct from the medullated fibres 

 to the dentine, but when the ' end cells ' are fully stained 

 it is seen that none of these strands pass direct to the dentine 

 but they all enter the ' end cell ' before their final distribu- 

 tion. These bodies have so long eluded observation because 

 they remain transparent and invisible even in preparations 

 in which the nerve fibres are very completely demonstrated. 

 Further experiment, however, showed that in these 

 cases the gold had not been thoroughly reduced, and unless 

 the reduction is very complete, the pulp showing a deep 



