VESICULAR OR GANGLIONIC NERVE-SUBSTANCE. 77 



vesicular. These nerve-vesicles, sometimes known as gan- 

 glion-globules, may be regarded as originally spherical, or 

 nearly so, in form (fig. 23, a); but they often present one or 

 more prolonged extensions ; and as these when single re- 

 semble tails, and when multiple are like the rays proceeding 

 from a star, the cells are said in the first case to be "caudate," 



Fig. 23. VESICULAR NERVE-SUBSTANCE. 



A, combination of Ganglion-cells (of which one is shown separately at a, more highly 

 magnified), and Nerve-fibres in the grey substance of the brain, which is also 

 traversed by a capillary vessel, b; B B, Ganglionic cells with caudate pro- 

 longations. 



and in the second to be stellate (B). These prolongations 

 have been traced into continuity, in some instances, with the 

 axis-cylinders of nerve-tubes, whilst in other cases they seem 

 to unite with those proceeding from other vesicles. It is not by 

 any means certain, however, that the nerve- tubes thus connect 

 themselves with the nerve-vesicles in all instances ; since it 

 frequently appears as if the former passed in among the 

 latter, without coming into direct continuity with them. 

 Sometimes a ganglion-cell seems to lie in the course of a 

 tubular fibre, which enlarges to envelope it, and then con- 

 tracts again to its former dimensions. There can be no 

 reasonable doubt, however, that in some way or other the 

 nerve-fibres and the nerve-vesicles come into some kind of 

 communication in the ganglionic centres. The vesicles are 



