o38 AYERS. [Vol. VIII. 



region of iveak to that of relatively strong stimnlation.'" (Italics 

 mine.) "The ' ether effect,' as observed in the sciatic nerve 

 of the Frog, may be best explained by supposing that a partial 

 paralysis of the nerve by the drug converts what would 

 naturally be a strong into a weak irritation, and that this weak 

 irritation affects only the flexor group of muscles, because 

 these are, for some reason or other, more irritable than their 

 antagonists." The author, after citing the investigations of 

 Ritter, Rollett, Bour, and Lombard on this subject, concludes 

 with the following paragraph : "There seems, therefore, to be 

 no doubt that the flexor apparatus of the Frog's leg responds to 

 a feebler stimulation than the extensor, but whether the cause 

 of this difference lies in the nerve fibres, the muscle fibres or 

 in the mode of connection between the two, must be left for 

 future investigators to determine," and he adds the suggestion 

 that histological differences such as exist between the red and 

 white muscle of Rabbits may be found to obtain in the Frog's 

 antagonistic groups. I have quoted thus at length because 

 this important topic as clearly and concisely stated above, is 

 still further elucidated by an experiment which is performed 

 in the following manner. In a pithed Frog the sciatic was 

 exposed near the head of the femur, the nerve cut and sepa- 

 rated into its two branches, peroneal and tibial from the point 

 of natural bifurcation to the cut end. The nerves were then 

 placed on separate electrodes and stimulated with equal cur- 

 rents, graduated by means of a telephone, and results noted 

 through a series of variations of the intensity and rate. The 

 main results are as follows : — 



1. Stimulation of Peroneal nerve alojte with all R and I. 

 produced complete flexion of leg and foot and abduction of the 



toes. 



2. Stimulation of the Tibial nerve alone with all R and I 

 produced complete extension of the leg and foot with adduction 

 of the toes. 



3. Stimulation of the Peroneal and Tibial together with low 

 I and R — produced flexion of leg and foot and adduction of toes 

 but with high I and R always extension of leg and foot and 

 abduction of the toes. 



