STROPHANTHUS SARMENTOSUS : ITS PHARMACOLOGICAL ACTION. 



373 



Experiment XLIX. — continued. 



Interval. 



Maximum Position of the Secondary Coil 



in mm. at which a Single-break Shock 



was effective. 



Notes. 



Muscles. 



Nerves. 



A. 

 mm. 



B. 

 mm. 



0. 



mm. 



A. 

 mm. 



B. 



mm. 



c. 



mm. 



After Immersion 

 in Minutes. 



70 



75 



80 



82 



85 



90 



93 



95 

 100 

 103 

 105 

 110 

 115 

 116 



120 

 125 

 130 

 135 

 140 

 142 

 145 

 150 

 155 

 160 

 165 

 170 

 175 



176 



330 



240 



220 

 250 

 220 



250 

 220 

 250 



230 

 180 

 180 



200 



330 

 210 



170 



160 



200 



230 

 240 

 170 



180 

 120 

 160 



110 



300 

 220 



180 



180 



220 



210 

 130 

 180 



130 

 100 



70 



80 

















 





 





 

 

 



















 





 







6 





 





380 



360 



410 



400 

 400 



380 

 350 



400 



340 



320 







Strong fibrillary twitches in C after stimulation. 

 A few fibrillary twitches in C only. 



Do. do. 

 Spontaneous strong fibrillary twitches in C. 



Slight fibrillary twitches in C after stimulation. 

 Do. without stimulation. 

 Do. after stimulation. 



Do. without stimulation. 

 Do. 



Slight fibrillary twitches in C without stimula- 

 tion ; none ever in A or B. 



Very slight fibrillary twitches in C. ■ 



Do. do. 

 No fibrillary twitches in A, B, or C. 

 Slight do. in C. , 

 No do. in A, B, or C. 

 Slight do. in C. 

 Slight do. in C. 



Very slight do. in C. 



No fibrillary twitches in A, B, or C. 



C does not respond to stimulation of its nerve ; 



no fibrillary twitches. 

 No fibrillary twitches in A, B, or C. Muscle C 



is pale and rigid. 



Twenty-two hours after immersion, muscle C did not respond to strong electrical 

 stimuli applied directly to the muscle ; after the same interval of time, muscle A 

 contracted slightly when directly stimulated with the secondary coil at 60 mm., and 

 muscle B contracted when directly stimulated with the secondary coil at 40 mm. 



Accordingly, the muscles whose motor nerve-ends were paralysed by curara did not 

 exhibit fibrillary twitches when poisoned by S. sarmentosus. It is by an action on the 

 motor nerve-ends in muscle, therefore, that the fibrillary twitches are produced. Very 

 soon after the fibrillary twitches cease, stimulation of the motor nerve-trunk fails to 

 cause contraction of its muscle. 



TRANS. ROY. SOC. EDIN., VOL. XLVII. PART II. (NO. 15). 56 



