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Scientific Proceedings (129) 



periment in our series indicate progressive changes in the con- 

 figuration and amplitude of the contractions as the nervous 

 paralysis brought about by the nicotin advances. These tracings 

 will be analyzed in detail in a later paper, A few of the more 

 striking changes may be stated as follows : Both in the stomach 

 and intestine, before the administration of nicotin, the rhythmic 

 contractions vary greatly in amplitude and are commonly super- 

 imposed on large tone changes. As the nicotin paralysis ad- 

 vances the tone changes subside and the amplitude of the con- 

 tractions, while becoming more uniform, diminishes greatly until 

 a stage is reached at which apparently certain inhibitory in- 

 fluences are removed and the amplitude of the contractions in- 

 creases suddenly and markedly. After this the rhythmic con- 

 tractions continue with a high degree of regularity. As the 

 nicotin paralysis is carried still farther the amplitude of the con- 

 tractions gradually decreases but is still relatively large when 

 electrical stimulation of postganglionic sympathetic fibers is no 

 longer effective. If the administration of nicotin is discontinued 

 at this point the rhythmic contractions continue without marked 

 changes in amplitude. 



We do not maintain that the tracings recorded before the ad- 

 ministration of nicotin in these experiments represent the exact 

 configuration of the contractions going on in the stomach and 

 intestine under normal conditions. Nevertheless, we believe 

 that the changes which occur in the tracings during the progress 

 of the nicotin paralysis represent actual changes in the muscular 

 activity which are due largely to the elimination of nervous in- 

 fluences. Doubtless, rhythmic contractions in the gastroin- 

 testinal canal are normally subject, in a large degree, to nervous 

 control. 



