OF THE CALABAR BEAN. 725 



distilled water, were injected into the lower portion of the abdominal cavity. It continued to 

 jump about for four minutes ; in five minutes, the first indications of paralysis occurred, at the 

 anterior extremities ; and in twenty-five, it was lying flaccid on its belly and chest, without 

 any respiratory movements, but with retained reflex action. The sympoms advanced in their 

 usual order until the complete death of the frog. 



An action on the cerebrum cannot, therefore, be the cause of the paralysed 

 condition which is produced. The cerebrum may, notwithstanding, be acted on by 

 physostigma; and the results of several experiments, in which I took various 

 quantities of this substance, appear to favour such an opinion, though, until 

 further investigation, I cannot maintain that the effects produced were not 

 mainly dependent on those perturbations of the circulation which are caused by 

 this poison. 



Action on the Spinal Nerves. 

 1. Motor or Efferent Nerve- Fibres. 



Experiment XVII. 



I injected into the jugular vein of a very large retriever dog, seven grains of extract, 

 suspended in twenty-five minims of distilled water. In three minutes, respiration became 

 gasping ; in five, the usual twitching affection of the muscles commenced ; and in ten, the 

 dog was lying in a powerless condition. In twenty minutes, respiratory and cardiac action 

 had completely ceased. The right sciatic nerve was then exposed, and galvanic stimulation of 

 its trunk produced vigorous movements confined to the leg whose nerve was stimulated. The 

 same result was obtained when the left sciatic nerve was exposed and stimulated. Both retained 

 their motor conductivity for eight minutes after respiration had ceased ; and, for some time 

 longer, the muscles responded to direct galvanic stimulation. 



Experiment XVIII. 



Five grains of extract were mixed with thirty minims of distilled water, and injected into 

 the abdominal cavity of a large and healthy female cat. Trembling occurred in four minutes, 

 when the cat ran a short distance and fell on her face, after which she lay in any position, 

 flaccid and unresisting. Bespiration ceased in ten minutes, but the peculiar twitching of the 

 muscles continued for several minutes longer. The heart was then exposed, and found motion- 

 less and full. On galvanising the sciatics, or otherwise stimulating them, the muscles of the 

 posterior extremities contracted vigorously ; but no evidence was obtained of the reflex activity 

 of the cord. The sciatic nerves continued active until forty-two minutes after the death of the 

 animal (fifty-two after the administration of the poison); but, when they were galvanised at 

 forty-seven minutes after death, no muscular contraction was produced. The phrenic and 

 brachial nerves also continued active for about the same time. 



Experiment XIX. 



Three grains of extract, suspended in eleven minims of distilled water, were injected into 

 the subcutaneous cellular tissue in the flank of a full-grown rabbit. Trembling occurred in two 

 minutes, and this continued, with varying strength, until seven minutes ; two minutes before 

 which respiration had ceased. The sciatic, phrenic and brachial nerves were galvanised, and 

 found to be active ; and such stimulation of the sciatics continued to produce muscular contrac- 

 tion until nine minutes after the cardiac and the respiratory movements had ceased. 



