CUTAIfEOUS NEBVE-TEEMINATIONS IN MAMMALS. 559 



tions, we are not inclined to found any special anatomical theory 

 upon it, and therefore cannot accept Professor Ranvier's theory 

 of '' disqties tactiles et cellules du tact^'' 



As mentioned, however, by Eanvier, the great mass of these 

 cells lie in the same direction, the liglit-grey body of the cell 

 with its nucleus generally visible, lying towards the root of the 

 hair when seen from the front ; but when looked at obliquely, as 

 at fig. 10, PI. XIV., the whole appears as an ordinary stellate 

 nerve-cell, identical in shape with those seen in the anterior 

 columns of the spinal cord, with which, in our opinion, they are 

 physiologically and anatomically identical. 



The manner in which the nerves reach the cells has been dif- 

 ferently described by various observers, but best by Bonnet and 

 E-anvier. It must be admitted also that no one description 

 applies to the many different ways in which a nerve arrives at, 

 or is distributed to, the cells. The side view given in our fig. 12 

 corresponds almost literally with the description given by Eanvier. 

 The nerve there loses its myeline when about to traverse the 

 basement-membrane. After piercing through it, it passes beyond 

 the first range of cells of the epidermic lining of the follicle (not 

 inserted in the drawing, lest they should interfere with the clear- 

 ness), then curves downwards with a bend whose convexity lies 

 next to and is parallel with the axis of the hair, until it returns to 

 the said lower layer of cells on the surface of the basement-mem- 

 brane, where it becomes attached to various of the nerve-cells, 

 and through these to many other cells, with which they are con- 

 nected by fibres. These otlier cells have not been inserted in the 

 drawing, as they could only be seen by great alteration of the 

 focus, and, if drawn, would have greatly confused the drawing. 

 All of these cells do not lie close to the basement-membrane, like 

 cell 5, which corresponds to the lower layer of epidermic ceUs ; 

 for the nerve-cell a corresponds almost to the second layer ; and 

 when we come subsequently to speak of the cells of Langerhans 

 (p. 584), we shall see that the nerve-cells we have been consider- 

 ing may break away from their attachments and become free 

 amongst the epidermic cells lining the follicle. 



The above description of the course and relations of a nerve at 

 its termination or, shall we say, origin in nerve-cells, gives only 

 an imperfect idea of the direction of the fibre or fibres after they 

 have lost their myeline-sheath. In fig. 10 we give a front view 

 of the ramifications ; and it is there seen that the fibrils resulting 



