Gastric and Duodenal Peristalsis in Rabbits. 15 
the irritability of the peripheral end of the sciatic nerve during 
the entire course of the experiment. It was found in every ex- 
periment that stimulation of the sciatic nerve even at the time of 
complete paralysis of respiration did not fail to elicit a definite 
motor response. This disposes of the second hypothesis; the 
paralysis is surely not due to a curare-like action of the sodium 
chloride. The first hypothesis we have tested in various ways. 
It is known that the twitchings of frog muscles in sodium chloride 
subside when calcium is added to the solution. We have therefore 
tried to introduce at some stage of the experiment solutions of 
calcium chloride into the circulation. In none of these experiments 
were the twitchings or the convulsions affected in any way by the 
addition of the calcium solution. Furthermore when the sciatic 
nerve was cut on one side the muscles innervated by this nerve 
did not take part in the twitching and convulsions. This fact 
was more strikingly demonstrated in experiments in which the 
lower half of the spinal cord was removed. In these cases the 
contrast between the convulsing upper half and the paralyzed 
lower half of the animal body was striking indeed. 
It is therefore evident that the convulsions and paralysis 
caused by hypertonic solutions of sodium chloride have their 
origin neither in the muscles nor in the peripheral nerves; they 
originate in the spinal cord. 
We may append here the brief remark that the convulsions 
under discussion can be greatly inhibited by intravenous injection 
of a non-fatal dose of potassium cyanide. We were stimulated to 
this latter observation by the known experiments of Loeb on 
the action of cyanide upon the fertilized and non-fertilized sea- 
urchin eggs. 
11 (536) 
Simultaneous graphic registration of gastric and duodenal 
peristalsis in rabbits ; a demonstration. 
By DON E. JOSEPH and S. J. MELTZER. 
[From the Department of Physiology and Pharmacology of the 
Rockefeller Institute for Medical Research.] 
The graphic registration of gastric or intestinal peristalsis is 
usually obtained from an animal with an opened abdomen while 
