150 TURNER, ON NERVE-FIBRES. 



simple or compound dilatations or diverticula. He con- 

 siders the glandular vesicles to be nothing more than these 

 dilatations. In my examination of the injected pancreas, I 

 have not succeeded in sufficiently separating from each other 

 the various follicles making up a lobule, so as to state whether 

 the view of Professor Kolliker can be applied to the pancreas. 

 Whether we hold, however, with the more generally accepted 

 doctrine, that these follicles are saccular dilatations at the 

 extremity of the duct, or with Professor Kolliker that they 

 are produced by a coiling of the duct upon itself, the impor- 

 tant fact still remains, that the membrane forming the wall 

 of the follicles is connected with that forming the wall of the 

 duct, and that the cavity of the one is continuous with that of 

 the other. 



In this communication I have avoided the use of the term 

 acini, as it has been employed by different observers to express 

 different structures, so that its use is liable to lead to con- 

 fusion of ideas ; some applying the term to express the ulti- 

 mate lobules of the gland, whilst by others it is used to signify 

 the ultimate follicles of these lobules. 



Further Observations on the Structure of Nerve-Fibres. 

 By Wm, Turner, M.B. (Lond.), Senior Demonstrator 

 of Anatomy, University of Edinburgh. 



In the number of this Journal for October, 1859, appeared 

 a communication by Professor Lister and myself, ' On the 

 Structure of Nerve-Fibres/ In it we directed attention to 

 the great benefits to be derived from the use of chromic acid 

 and carmine in the examination of these fibres. We espe- 

 cially pointed out the different action of these two substances 

 upon the constituent structures of the fibres, the axial 

 cylinders alone being coloured by the carmine, whilst the 

 medullary sheaths assumed under the action of the chromic 

 acid a peculiar fibroid appearance. Our observations were 

 made especially upon transverse sections through the fibres, 

 not only as they exist in an ordinary spinal nerve, such as 

 the sciatic, but also as they lie in the columnar portions of 

 the cord. In addition, wc described and figured certain 

 fibres, views of which were obtained by making longitudinal 

 sections of the columnar portions of the cord. Since this 

 paper was printed, I have continued my observations on the 

 subject, and, by a slight modification of our former process 



