Literary Notices, xxix 



An acceptance of both theories, as is done by Fleming, if we read 

 him correctly, is objectionable in that it must be assumed that certain 

 axis-cyhnders develop wholly or in part from cells of ectodermal origin, 

 while others in at least a portion of their course develop from cells of 

 mesenchymal origin (neuroblasts developed from neurilemma nuclei). 



The early return of sensation in cases of secondary nerve suture is 

 as difficult to explain by the one theory as by the other. The early 

 union of the peripherally developed young axis-cylinders (peripheral 

 theory) with the traumatically injured peripheral ends of the central 

 portion of a nerve after secondary suture does not seem probable and 

 is not born out by experimental proof. G. c. H. 



The Healing of Neryes.^ 



This research of Ballance and Stewart was undertaken to as- 

 certain the "exact process whereby peripheral nerves, after they have 

 been divided, become reunited," consideration being given to both the 

 degenerative and regenerative processes involved. The observations 

 recorded are based, in the main, on data gained by experimentation on 

 monkeys, dogs, cats and rabbits; material obtained during the opera- 

 tion for secondary nerve suture in man was also studied microscopically 

 and is discussed. The nature of the experimental work was as follows: 

 In certain of the experiments, the nerve was exposed, divided and 

 immediately sutured; in others, a large nerve was divided, the cut 

 ends being left unsutured; in still others, a segment of a nerve was ex- 

 cised, and after periods varying in the different experiments, a portion 

 of nerve sufficient to fill the gap was transplanted. In all, nearly 150 

 experiments were made. The animals were left after severance of the 

 nerve, for periods varying in the different experiments. The tissues, 

 after fixation in Muller's fluid, or in solutions of formalin, were 

 stained by one of the following four methods: 



"i. Weigert's method of selective staining of the medullary 

 sheaths. 



2. Cox's modification of the Golgi method for the impregnation 

 of axis cylinders. 



3. Stroebe's method for staining of the axis cylinders. 



4. Van Gieson's method for the staining of the cellular and pro- 

 toplasmic structures." 



^Charles A. Ballance, M. S., F. R. C. S., and Purves Stewart, M. A., 

 M. I>., M. R. C. P. The Healing of Nerves. Monograph, 112 pp., sixteen 

 plates and one text figure. Macmillan ^ Co., 1 901. 



