666 HUBER. [Vol. XI. 



results obtained in my own experiments will be presented at 

 the end of this paper. 



Part II, — Record of Experiments and Physiological 



Examinations. 



As has been previously stated, the aim of this research has 

 been, — to try, experimentally, the various methods suggested 

 for repairing loss of substance in peripheral nerves, when such 

 loss is so great that the ends of the divided nerve cannot be 

 brought together by the ordinary methods of nerve suture ; to 

 find out, if possible, which one of the many methods used is 

 likely to give the most favorable result ; to obtain some idea of 

 the time required for the return of function to the peripheral 

 end ; and to establish the structural changes which take place 

 during degeneration and regeneration. The experimental work 

 has, therefore, been partly physiological and partly histological. 

 The record of the experiments and the physiological observa- 

 tions made will form one part of this paper, and the results 

 obtained from microscopical examination of the preparations 

 will be recorded in another part. 



The animals used for operations were dogs. With but few 

 exceptions the ulnar nerve was selected for experimentation ; 

 in some few instances the median or sciatic was used. At the 

 time of operation and examination the animals were narco- 

 tized with large doses of morphia sulphate injected hypoderm- 

 ically in the inguinal region, and, if thought necessary, this 

 was followed by ether. Antiseptic precautions were observed 

 with as much detail as can well be indulged in when the 

 operations have to be performed in a general laboratory. The 

 hair over the course of the nerve selected for the operation and 

 the surrounding parts was removed with a razor, and the skin 

 thoroughly washed, first, with soap and water, and then with a 

 five per cent carbolic acid solution. The animal was then covered 

 with towels sterilized by steam. The instruments and sponges 

 were sterilized in the same way, and while operating the instru- 

 ments were kept in a two and one-half per cent carbolic acid 

 solution, and the sponges in a ^qVo bichloride of mercury 



