DR THOMAS R, FRASER ON STROPHANTHUS HISPIDUS. 453 



followed by slowing after strophanthin began to be administered ; but this slowing 

 was only inconsiderable, and even after the last (fifth) dose of strophanthin, the pulse- 

 rate immediately before death was so rapid as 174 in the minute. When the blood- 

 pressure was high as well as when it was low, the pulse-rate was at times slow and at 

 times rapid. 



The pulse movements were markedly increased in size by strophanthin, notwith- 

 standing the repeated administration of atropine ; and large and uniform movements 

 occurred, both when the pressure was about the normal as well as when it was much 

 above it. This increase of pulse movement was exhibited while the vagus cardio- 

 inhibition was much weakened, and even when, apparently, it was paralysed by atropine 

 (see Tracing Nos. 4, 10 and 11). 



The usual effects of strophanthin on respiration, as well as on the pulse-rate, were 

 interfered with by atropine, as the respirations remained above or at the original rate 

 until a few seconds before death. 



In fact, the administration of atropine failed in preventing strophanthin from 

 producing its usual effects on blood-pressure and on the size of the pulse movements, 

 although it succeeded in lessening its effects on the rate of the pulse and of respira- 

 tion. 



Further, the experiment suggests that the paralysing action of atropine on the 

 cardio-inhibitory function of the vagus is lessened by strophanthin, for, notwithstanding 

 the repeated administration of atropine, considerable difficulty was encountered in main- 

 taining paralysis of the vagus throughout the experiment. 



These experiments (CXLVL, CXLVIL. CXLVIIL, CXLIX., and CL.), therefore, 

 appear to confirm the experiments on frogs by affording evidence of there being but 

 little action produced by Strophanthus on the blood-vessels ; of there being a powerful 

 action produced on the heart, whereby both the diastolic expansion and the systolic 

 contraction of that organ are much increased ; and of there being no necessary implica- 

 tion of the cardio-inhibitory function of the vagus in the production of the diastolic 

 expansion, which constitutes so prominent a feature of the action of Strophanthus upon 

 the heart. 



E. Action on the Lymph-Hearts of the Frog. 



Notwithstanding the powerful action of Strophanthus upon the blood-heart, it affects 

 the lymph-hearts only feebly and slowly. In the experiment illustrative of this state- 

 ment, the dose administered was a large one. 



Experiment CLI. — The posterior lymph-hearts were exposed in a frog, weighing 340 

 grains. They were pulsating, nearly regularly, at the rate of 18 per 30 sec. One-tenth 

 of a grain of extract of Strophanthus was injected under the skin at the thorax. The 

 lymph-hearts were continuously observed, and it was found that their pulsations con- 

 tinued at the rate of from 15 to 21 per 30 sec. during the 20 min. succeeding the 



