Literary Notices. cxxxvii 



difliciilty of aftectiiii,^ connections (in the end-plates of muscles, for ex- 

 ample.) 



6. I,ig;ht mechanical stimuli were often more effective in exciting 

 the fibres in an early stage of regeneration than electrical induction 

 shocks. [-May this not be due to the greater autonomy of the segments 

 and the functional activity of the local elements during this stage?. — Ed.] 



7. Conductivity is restored before irritability; but these embryonic 

 fibres respond to mechanical imi^ulse when not to electric shock. [See 

 remark above.] 



<S. The possibility of the functional union of two spinal nerves was 

 proven. The central end of the median was united to the peripheral end 

 of the ulnar nerve and the peripheral stump of the median and the cen- 

 tral stump of the ulnar were dissected away. P'unctional union occurred 

 and the animal was examined after 75 days. The physiological results of 

 the union were unfortunately poorly differentiated. 



In the histological study the best results were obtained by the method 

 of teasing. The fresh nerve was pinned out, hardened and stained in osmic 

 caid 24 hours, then washed in water 24 hours or six to seven clays. Next it 

 was partially teased, stained in Boehmer's hematoxylin and examined by 

 teasing on the slide in glycerine or Farrant's solution. Other nerves 

 were hardened in Mueller's fluid, then, after partial teasing, were stained 

 by Freud's potash-gold method and treated with hrematoxylin for nuclei. 

 This method brings out the axis cylinder. A third method is recom- 

 mended, which consists in pinning out in picvic acid, saturated solution, 

 48 hours. They were then washed out in water 5 or 6 hours and subse- 

 quently in ^;} and 50 per cent, alcohol and preserved in 95 per cent. 

 They were then partially teased and stained 10-15 minutes in Btehmer's 

 hiematoxylin The process seems to expose the axis cylinder by re- 

 moval of the myelin. 



" After the interruption of the connection fjetween a nerve fibre and 

 its centre, whether the interruption be by actual section, b)' crushing, or 

 by coagulation, the peripheral end of the fibre undergoes degeneration, 

 the changes affecting first the myeline and the axis, and subsequently the 

 sheath and its nuclei." The degeneration begins, in the dog, after about 

 4 days. The fragmentation of the myelin sheath (at the lines of Lanter- 

 mann) is regarded as independent of and prior to the increase of proto- 

 plasm about the nuclei. The axis cylinder breaks up with the myelin 



