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Dr. H. Kronecker and Mr. S. Meltzer. [Nov. 17, 



centims. from tlie lower border of the pharynx, the contraction lasted 

 2 — 3 seconds, and in the deep portion, about 12 centims. in extent 

 from the cardia, 8 — 9 seconds, and that the transition from the region 

 of shorter to that of longer contraction occurred in a short portion, 

 about 4 centims. long, about the level of the manubrium sterni. It is 

 a physiological characteristic of this region that in it the transition 

 from the striated to the smooth muscles occurs (E. Weber). 



In determining the period of latent stimulation for the purpose of 

 measuring the speed of propagation of the peristaltic waves, it was 

 found that the period increased not gradually but by bounds. Thus, 

 in the upper portion of the oesophagus, 8 centims. long, measuring 

 from the beginning, the period of latent stimulation amounts to from 

 1 to 1*5 seconds; in the following portion, 8 centims. long, from 3 to 

 35 seconds, and in the undermost portion, from about 5"5 to 7 

 seconds. From these researches it appeared highly probable that the 

 reflex ganglia of deglutition are arranged in three groups connected 

 with one another. But the experiments seemed also to show that 

 there must be a fourth group, placed near to the other three, through 

 which the first reflex of the act of swallowing occurs. This upper- 

 most group is more closely related with the lower three than these 

 with one another, since we have found that the three regions of the 

 oesophagus can contract, from above downwards in orderly sequence, 

 without a first act of swallowing having occurred. This happens in 

 consequence of "eructation," which effects a separate irritation on 

 the three lower ganglion groups of deglutition. 



When one makes a series of acts of swallowing quickly one after 

 the other, as in drinking a glass of water, the registering ball shows 

 that one oesophageal contraction follows, and that only after the last of 

 the series; and its occurrence is timed, in reference to the last draught, 

 as if it had been produced by a single act of swallowing. It therefore 

 appeared : — 



I. That the beginning of every act of swallowing not only excites 

 the oesophageal contraction related to it, but, at the same time, restrains 

 the contraction, excited shortly before, but ivhicli has not yet occurred. 

 This inhibition is capable of preventing the contraction even immediately 

 prior to its appearance. 



It is therefore to be concluded that the restraining excitation, 

 traversing the direct motor tracts, outruns the motor excitation, 

 advancing through the ganglion groups. 



If a second act of swallowing occurs when the oesophageal con- 

 traction, following the first, has already begun, this contraction can no 

 longer be restrained. In such a case, however, the contraction 

 corresponding to the second act begins as late as if this second act 

 had not been performed till after the completion of the first contrac- 

 tion. In other words : — 



