746 



DR FRASER ON THE PHYSIOLOGICAL ACTION 



14 minutes afterwards, cardiac contractions = 14 per min. Systole not quite so pale as originally. 



c Frog is quite flaccid ; it cannot turn 



16 



18 

 20 



22 



= 11 



= 10 



= 7 



= 



< from its back, but occasional faint 

 V. struggles occur. 

 Contractions very feeble. 



(Heart as dark during contraction of 

 the ventricles as during dilatation of 

 them. 

 Irregular and non - synchronous ; 

 the auricles sometimes contract- 

 ting nine or eleven times per 

 minute, 

 of ventricles, 10 of auricles. 

 14 

 14 



8 „ „ 14 



during one minute, and then a few feeble con- 

 tractions in the auricles, and again a pause. 

 per min. 

 „ 



„ of ventricles, 3 of auricles. 

 » » 12 „ 



16 

 16 

 ,, Synchronous. 

 „ Skin extremely dark. 



{No reflex movement on stimulation. 

 Galvanism of the sciatic nerves 

 causes faint twitches of the toes. 

 C All the spinal nerves are paralysed ; 

 „ -\ the muscles remaining active and 

 I blue. 



The observations were now interrupted until twenty hours after the exhibition of the poison, 

 and, at this time, the frog was quite flaccid and dark; the heart was contracting sixteen times in 

 the minute, and the striped muscles were irritable, but otherwise the animal was quite dead. 

 Twenty-eight hours after the exhibition of Calabar bean, the cardiac contractions were 

 seventeen per minute ; and at thirty hours they were ten. In forty hours, the heart was found 

 perfectly still, dark and somewhat dilated. Direct galvanism produced a slow contraction of 

 the portion of cardiac muscle included in the circuit ; it did not excite a normal heart beat. 

 The striped muscles contracted very sluggishly when galvanised. This idio-muscular con- 

 tractility was retained in the heart until sixty-nine hours, and in the striped muscles till seventy 

 hours after the administration of the poison. They then became pale, stiff and acid. 



In this experiment, a large proportion of the extract had not been absorbed, 



but escaped from the thighs when the skin was incised to allow the sciatic nerves 



to be exposed. The effects cannot, therefore, be regarded as those produced by 



five grains, but must be held to have been caused by a much smaller quantity. 



Indeed, where three grains were absorbed by a frog of nearly the same weight, 



the action on the heart was much more decided and marked. 



24 



39 3 



26 



39 3 



28 



99 3 



30 



>." 3 



32 



39 33 



34 



39 3 



36 



9T y> 



38 



39 33 



40 



» 33 



42 



39 33 



45 



» 33 



50 



33 3 



55 



79 3 



1 houi 



min. „ 



1 „ 



10 n 



1 „ 



15 „ 



1 „ 



20 „ 



2 hours „ , 



3 „ 



„ 



