In the first paper1 of this series, the important question of peristolic function was summarily mentioned. In view of the significant and successful practical application made possible by the definite acceptance of this function as a basis for reasoning, I wish to devote this paper to a more detailed explanation of our procedure and the results obtained.
We became aware of the existence of the peristolic reflex in the course of our roentgenographic work on the gastric functions in infants. As our study progressed, and our observations increased in number, we were able to establish with absolute certainty the existence of a so-called "peristolic function" of the stomach, entirely different from and not to be confused with the more familiar peristaltic function.
It is perhaps best at this point to define terms. Peristalsis may be described as a circular wave of contraction, appearing at regular intervals, which begins at