DR THOMAS R. FRASER ON STROPHANTHUS HISPIDUS. 391 



the auricles continued irregularly, at the rate of 6 per 30 sec. In 1 hour 7 min., the 

 auricles also ceased to contract. They were dark and distended, while the ventricle was 

 pale and small. Throat respirations still occurred, at irregular intervals, and they were 

 observed also 9 min. afterwards. In 1 hour 20 min., irritation of the surface of 

 the ventricle caused an extremely feeble movement ; while irritation of the surface of the 

 auricles caused a series of contractions limited to the auricles, and continuing for 1 

 min. In 1 hour 23 min., irritation of the ventricle produced no effect ; and of the 

 •surface of the auricles, a single contraction followed by complete rest. In 1 hour 41 min., 

 galvanic irritation, even when powerful, applied to various parts of the ventricle and 

 auricles produced no movement of the heart, but it excited strong local contractions of 

 the skeletal muscles and well-marked general movements of the body. 



The changes produced in the heart's action by large doses of Strophanthus are 

 therefore seen to be slowing of its rate with prolongation of the ventricular systole ; 

 irregular and arhythmical contractions of the heart ; imperfect diastolic dilatation of 

 the ventricle, producing " pouchings " of its walls ; and, finally, standstill of the ven- 

 tricle in extreme systolic contraction. In this final standstill, the ventricle is small, 

 pale, and rigid ; it contains almost no blood ; it is incapable of resuming contraction, 

 whatever be the stimulation to which it is subjected ; and the reaction of its muscle 

 soon becomes acid. 



After the ventricle has become permanently non-contractile, the auricles, however, 

 continue to contract for many minutes, though, latterly, in an irregular manner ; and 

 when they have ceased to contract, they are large and dark, and they remain in this 

 state for several hours. 



Although the effects of large doses upon the heart have not been followed, in their 

 various stages, in warm-blooded animals, the appearances presented when the heart was 

 examined soon after death indicate that the final ventricular standstill is in them of the 

 same nature, and render it probable that the changes preceding standstill are also of the 

 same character as in frogs (see Experiments IX., XXXV., and XXXVI. ). 



In the next experiment it is shown that the changes produced in the heart's action 

 by small doses of Strophanthus are, in many respects, widely different from those 

 produced by large doses. 



Experiment LXXIV. — A frog, weighing 320 grains, received by subcutaneous injection 

 0*00025 grain of strophanthin ( = 0*000078 grain per 100 grains) in 4 minims of water. 

 The thoracic extremities became, bye and bye, unduly extended, and the voluntary move- 

 ments sluggish ; but no other important symptoms were observed during three hours and 

 a half following the injection. 



On the following day, 22 hours after the injection, the posture was natural, and 

 respiratory movements were occurring, but the frog had considerable difficulty in jumping. 

 The heart was now exposed, after the frog had been pithed, and at 22 hours 25 min. 

 after the injection, the following was noted : — Heart motionless and very large and dark, 

 and it continued so for two minutes and a half ; struggles and respiratory movements 



VOL. XXXVI. PART II. (NO. 16). 3 O 



