THE NERVOUS SYSTEM- 165 



the latter were not cells which afterwards divide ? — because 

 divisions of the nerve-cells undoubtedly take- place (vid. infra), — 

 and in this way become unipolar ; 4. whether the cells give off 

 one or two fibres, one of the latter does not go towards the 

 centre and the other towards the periphery, but both proceed 

 in the latter direction; at all events, in the examination of all 

 small ganglia, only such ganglion-fibres are visible. Stannins, 

 in bipolar-cells of this kind from the Calf, also found the two 

 processes closely approximated ; 5. it is difficult to determine 

 whether cells without processes also occur in the spinal ganglia, 

 seeing that the processes are very readily detached, and that 

 cells thus truncated may very easily be regarded as apolar 

 cells. In small ganglia in the Mammalia a fibre may be traced 

 to each cell, whilst in the smallest spinal ganglia in Man, and 

 in the inconstant ganglia of the posterior roots (vid. seq.) } cells 

 are not unfrequcntly met with, to which no fibre is attached, 

 and, consequently, I would, at present, merely state that, in any 

 case, fibres arise from the majority of the cells. In order to 

 examine these conditions, either the larger ganglia in Man 

 are selected, which are torn into fibres as carefully as possible 

 under a simple microscope, until the fibres are traced to their 

 origin, which may be done with a little trouble in almost every 

 ganglion, or the small ganglia of the fifth sacral and coccygeal 

 nerves are taken for the purpose. In these ganglia, in almost 

 every individual, solitary and completely isolated, pedunculated, 

 gangliou-globnlcs are met with, close to or in the neighbourhood 

 of the ganglia, each in its special sheath, which in this case 

 appears to be homogeneous (fig. 157), and in many cases, the 

 .simple, dark nerve-fibre lying in the peduncle of the globule, 

 and frequently also its connection with the cell, by means of 

 a pale process, may be distinctly perceived. In the ganglia 

 aberrantia also of Hyrtl, that is to say the inconstant, larger 

 or smaller collections of nerve-cells, which are found in every 

 subject upon the posterior roots of the larger nerves, the simple 

 origins of fibres may occasionally be distinctly noticed. The 

 dai'k-colourcd fibres, arising from the nerve-cells, simply con- 

 stitute the continuation of the pale processes of the cells, so 

 that the membranes and contents of each part pass con- 

 tinuously into each other, and thus also the membrane and 

 the contents of the cells are connected with the sheath of the 

 i. 30 



