7o8 HUBER. [Vol. XI. 



wound, as the record of the experiment shows that feeble 

 reflexes were observed. I may briefly summarize the above 

 results, and the "interpretation given them in the following 

 statement : many of the down-growing axis cylinders from the 

 central nerve fibres have reached the connective tissue layer 

 between the central stump and the implanted segment ; of 

 this number a very small per cent have reached the upper end 

 of the peripheral ulnar, some others the peripheral wound and 

 peripheral portion of the implanted segment, and a larger 

 number the middle and central end of the implanted nerve. 

 The regeneration of the peripheral ulnar is far advanced by 

 the end of the fourth month. A review of the results obtained 

 at the physiological examination in Exps. 17, 19, and 20, 

 show a return of function to the motor fibres going to flex, 

 carp, ul., and also that the sensory fibres have the power of 

 conducting impulses, at least down to the middle of the 

 forearm (Exp. 19). Microscopical examination corroborates 

 these conclusions. It is at this time very easy in longitudinal 

 sections to trace the axis cylinders of the fibres in the central 

 end through the connective tissue into the upper end of the 

 implanted segment. Usually the old axis cylinder ends in a 

 slight enlargement, from which, or from the axis cylinder just 

 above it, a smaller thread, stained deeply in anilin blue, the 

 new axis cylinder, surrounded by a narrow sheath of myelin, 

 can be traced. Now and then an appearance shown in PI. 

 XXXV, Fig. 12, is seen. In such cases the central axis 

 cylinders would seem to have divided into several branches, 

 these growing for a longer or shorter distance toward the 

 periphery within the old sheath of Schwann. In the fibre 

 reproduced in the figure, only one of the new axis cylinders 

 becomes the axis of a nerve fibre ; the others are seen to end 

 in small bulbous enlargements. Similar observations have 

 been made by Ranvier, and by Howell and Huber (Fig. 60, 

 and not so well represented in Fig. 62), and very clearly 

 shown in Figs. 8, 9, and 10 of PI. VIII, illustrating Stroebe's 

 article. The course of the nerve fibres through the central 

 wound (the connective tissue between the central stump and 

 implanted segment) I have tried to represent in PI. XXXV, 



