168 



Dr. K H. Alcock. The Electromotive [Dec. 15, 



than is usual in the mammalia. It is not certain how far this is due to 

 the greater amount of connective tissue present between the individual 

 nerve-fibres, or to some other cause. 



Both current of injury and negative variation are considerably- 

 greater in the non-medullated nerves of the horse than in the 

 medullated. The following table gives the result of several 

 observations : — 



Table II. 



Nerve. 



Current of injury.* 



No. of 

 experi. 

 ments. 



Negative variation.* 



No. 

 of experi- 

 ments. 



Mean. 



Max. 



Mean. 



Max. 



Median .... 

 Splenic .... 



3-86 

 5-81 



5-3 

 15 -5 



5 

 13 



0-380 

 0-860 



83 

 2-3 



4 

 11 



These are the values obtained with the galvanometer. They are 

 probably too low, and for several reasons it is likely that the maximum 

 values are more nearly correct than the mean. They are, however, 

 strictly comparative, and it is seen the voltages in the splenic nerves 

 are approximately three times the median, a result agreeing with the 

 observations on cold-blooded animals, f The non-medullated nerves of 



Fia. 1 (Exp. 714, V.). — Splenic of Horse. The vertical lines are the successive 

 negative variations produced by tetanising currents (5000 Berne units, 2 volts 

 in primary circuit) for 13 seconds, repeated once a minute. 



* Here and elsewhere in millivolts. 



f Kuhne u. Steiner, ' Unters. d. Physiol. Inst. d. Univ. Heidelberg,' vol. 3, 

 p. 149 ; Sowton, ' Roy. Soc. Proc.,' vol. 66, p. 379. 



